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Lolu chungechunge lwabekwa kunqolobane. Uyacelwa ubuze umbuzo omusha uma udinga usizo.

Firefox Takes Up CPU; Process Will Not End

  • 20 uphendule
  • 28 zinale nkinga
  • 2 views
  • Igcine ukuphendulwa ngu John99

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Hi all! This is my first time in the forum and I'm hoping someone can help me. For about a month I've suffered a recurring problem. Every time I use Firefox, it immediately begins to take up about half of the CPU and Physical Memory. It hangs during use. When I go to close the program, the firefox.exe *32 process will not end and CPU/Memory use remain high. I can only close Firefox by ending the process through Windows task manager. Naturally, this also means that I cannot reset Firefox or use Firefox Safe Mode as diagnostic tools. I have seen a few people with similar problems saying that they solved theirs by deleting the program's secmod.db file, but I had no luck with that. Uninstalling/reinstalling Firefox has similarly had no effect. Has anyone else had this problem? For reference, I am running Windows 7 and Firefox 26.0.

Hi all! This is my first time in the forum and I'm hoping someone can help me. For about a month I've suffered a recurring problem. Every time I use Firefox, it immediately begins to take up about half of the CPU and Physical Memory. It hangs during use. When I go to close the program, the firefox.exe *32 process will not end and CPU/Memory use remain high. I can only close Firefox by ending the process through Windows task manager. Naturally, this also means that I cannot reset Firefox or use Firefox Safe Mode as diagnostic tools. I have seen a few people with similar problems saying that they solved theirs by deleting the program's secmod.db file, but I had no luck with that. Uninstalling/reinstalling Firefox has similarly had no effect. Has anyone else had this problem? For reference, I am running Windows 7 and Firefox 26.0.

Okulungisiwe ngu Obscurebookwyrm

All Replies (20)

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First of all try Firefox in its safe mode. Firefox does not need to be running. Holding the Keyboard Shift key whilst clicking on the icon should start in safe-mode

As Firefox starts and opens are you able to try to use about:memory ?

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Hi, John99. Thank you for your suggestions. Restarting Firefox in Safe Mode did not fix the problem. Nor did disabling all plugins. I noticed some improvement in that Firefox no longer takes up massive amounts of CPU while running, but sure enough - when I went to close the program, its CPU useage jumped to 50 and the amount of physical memory Task Manager indicated was in use spiked also. The process again would not end until I closed it manually in Task Manager.

I am noticing some additional problems. For one, Firefox cannot create .json bookmark backups (it creates files with 0 kb) or export bookmarks/settings to Chrome (Chrome crashes). Attempting to create a .html bookmark backup seems to be doable, but the pace was so slow that after more than 48 hours FF had not finished.

I did manage to run the memory report, and will attach it as soon as I can in case it helps.

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Main Process
Explicit Allocations
<pre>
75.18 MB (100.0%) -- explicit
├──20.28 MB (26.97%) -- js-non-window
│  ├──14.77 MB (19.65%) -- zones
│  │  ├──12.62 MB (16.79%) ++ zone(0x6a44800)
│  │  ├───1.94 MB (02.58%) -- zone(0xb73c00)
│  │  │   ├──1.91 MB (02.54%) -- strings
│  │  │   │  ├──1.52 MB (02.02%) -- normal
│  │  │   │  │  ├──1.11 MB (01.48%) ── malloc-heap
│  │  │   │  │  └──0.41 MB (00.54%) ── gc-heap
│  │  │   │  └──0.39 MB (00.52%) ++ (2 tiny)
│  │  │   └──0.03 MB (00.04%) ++ (3 tiny)
│  │  └───0.21 MB (00.28%) ++ (3 tiny)
│  ├───5.24 MB (06.97%) -- runtime
│  │   ├──2.92 MB (03.89%) ── script-data
│  │   ├──1.00 MB (01.33%) ── atoms-table
│  │   ├──0.94 MB (01.26%) ── script-sources
│  │   └──0.37 MB (00.49%) ++ (9 tiny)
│  └───0.27 MB (00.35%) ++ gc-heap
├──18.57 MB (24.71%) -- storage
│  ├──17.22 MB (22.91%) -- sqlite
│  │  ├───9.85 MB (13.11%) -- places.sqlite
│  │  │   ├──9.58 MB (12.74%) ── cache-used [4]
│  │  │   └──0.28 MB (00.37%) ++ (2 tiny)
│  │  ├───2.43 MB (03.24%) ── other
│  │  ├───2.05 MB (02.73%) -- webappsstore.sqlite
│  │  │   ├──2.04 MB (02.72%) ── cache-used [2]
│  │  │   └──0.01 MB (00.01%) ++ (2 tiny)
│  │  ├───1.90 MB (02.53%) -- cookies.sqlite
│  │  │   ├──1.88 MB (02.51%) ── cache-used
│  │  │   └──0.02 MB (00.02%) ++ (2 tiny)
│  │  ├───0.83 MB (01.10%) -- content-prefs.sqlite
│  │  │   ├──0.82 MB (01.09%) ── cache-used
│  │  │   └──0.01 MB (00.01%) ++ (2 tiny)
│  │  └───0.16 MB (00.21%) ++ (2 tiny)
│  └───1.35 MB (01.80%) -- prefix-set
│      ├──0.84 MB (01.11%) ── goog-phish-shavar
│      └──0.52 MB (00.69%) ++ (3 tiny)
├──10.72 MB (14.26%) -- window-objects
│  ├───4.43 MB (05.90%) -- top(http://www.winzip.com/lanall.htm?ext=GZ, id=8)
│  │   ├──2.97 MB (03.96%) -- active
│  │   │  ├──2.74 MB (03.64%) -- window(http://www.winzip.com/lanall.htm?ext=GZ)
│  │   │  │  ├──1.49 MB (01.99%) ++ js-compartment(http://www.winzip.com/lanall.htm?ext=GZ)
│  │   │  │  └──1.24 MB (01.65%) ++ (4 tiny)
│  │   │  └──0.24 MB (00.32%) ++ window(http://www.google.com/ads/user-lists/1004287606/?label=aKMxCPq34AQQ9uzw3gM&fmt=1&num=1&cv=7&frm=0&url=http%3A%2F%2Fwww.winzip.com%2Flanall.htm%3Fext%3DGZ&ref=http%3A%2F%2Fshell.windows.com%2Ffileassoc%2F0409%2Fxml%2Fredir.asp%3FEXT%3Dgz&random=2448438875)
│  │   ├──1.05 MB (01.39%) ++ js-zone(0xb07b000)
│  │   └──0.41 MB (00.55%) ++ cached/window(http://shell.windows.com/fileassoc/0409/xml/redir.asp?EXT=gz)
│  ├───3.66 MB (04.87%) -- top(chrome://browser/content/browser.xul, id=3)
│  │   ├──3.40 MB (04.53%) -- active
│  │   │  ├──3.36 MB (04.47%) -- window(chrome://browser/content/browser.xul)
│  │   │  │  ├──1.55 MB (02.06%) ++ js-compartment([System Principal], about:blank)
│  │   │  │  ├──0.93 MB (01.24%) ++ (3 tiny)
│  │   │  │  └──0.88 MB (01.17%) ++ layout
│  │   │  └──0.04 MB (00.05%) ++ window(about:blank)
│  │   └──0.26 MB (00.34%) ++ js-zone(0x7a36800)
│  ├───1.45 MB (01.93%) ++ (4 tiny)
│  └───1.18 MB (01.57%) ++ top(about:memory, id=21)
├───9.50 MB (12.64%) ── heap-unclassified
├───6.76 MB (09.00%) -- heap-overhead
│   ├──3.43 MB (04.57%) ── page-cache
│   ├──3.33 MB (04.42%) ── waste
│   └──0.00 MB (00.01%) ── bookkeeping
├───4.03 MB (05.36%) -- workers/workers()
│   ├──1.37 MB (01.83%) ++ worker(resource://gre/modules/PageThumbsWorker.js, 0xb008800)
│   ├──1.34 MB (01.78%) ++ worker(resource://gre/modules/osfile/osfile_async_worker.js, 0x7ad2400)
│   └──1.32 MB (01.75%) ++ worker(resource:///modules/sessionstore/SessionWorker.js, 0x80c5400)
├───2.41 MB (03.21%) ++ (15 tiny)
├───1.08 MB (01.44%) -- startup-cache
│   ├──1.08 MB (01.44%) ── mapping
│   └──0.00 MB (00.00%) ── data
├───0.95 MB (01.26%) ++ gfx
└───0.87 MB (01.15%) ── xpti-working-set

Other Measurements

7.25 MB (100.0%) -- decommitted
├──4.48 MB (61.80%) -- workers/workers()
│  ├──1.50 MB (20.64%) ── worker(resource://gre/modules/PageThumbsWorker.js, 0xb008800)/gc-heap/decommitted-arenas
│  ├──1.49 MB (20.58%) ── worker(resource:///modules/sessionstore/SessionWorker.js, 0x80c5400)/gc-heap/decommitted-arenas
│  └──1.49 MB (20.58%) ── worker(resource://gre/modules/osfile/osfile_async_worker.js, 0x7ad2400)/gc-heap/decommitted-arenas
└──2.77 MB (38.20%) ── js-non-window/gc-heap/decommitted-arenas

26.93 MB (100.0%) -- js-main-runtime
├──16.26 MB (60.38%) -- compartments
│  ├───7.53 MB (27.97%) -- shapes
│  │   ├──4.34 MB (16.10%) -- gc-heap
│  │   │  ├──2.35 MB (08.73%) -- tree
│  │   │  │  ├──2.09 MB (07.77%) ── global-parented
│  │   │  │  └──0.26 MB (00.96%) ── non-global-parented
│  │   │  ├──1.60 MB (05.94%) ── base
│  │   │  └──0.39 MB (01.44%) ── dict
│  │   └──3.19 MB (11.86%) -- malloc-heap
│  │      ├──2.40 MB (08.91%) ── compartment-tables
│  │      ├──0.40 MB (01.49%) ── tree-tables
│  │      └──0.40 MB (01.47%) ++ (2 tiny)
│  ├───6.22 MB (23.10%) -- objects
│  │   ├──4.65 MB (17.26%) -- gc-heap
│  │   │  ├──2.86 MB (10.62%) ── function
│  │   │  ├──1.30 MB (04.83%) ── ordinary
│  │   │  ├──0.33 MB (01.23%) ── dense-array
│  │   │  └──0.15 MB (00.57%) ── cross-compartment-wrapper
│  │   ├──1.57 MB (05.84%) -- malloc-heap
│  │   │  ├──1.50 MB (05.55%) ── slots
│  │   │  └──0.08 MB (00.29%) ++ (3 tiny)
│  │   └──0.00 MB (00.00%) ── non-heap/code/asm.js
│  ├───1.84 MB (06.82%) -- scripts
│  │   ├──1.53 MB (05.68%) ── gc-heap
│  │   └──0.31 MB (01.14%) ── malloc-heap/data
│  └───0.67 MB (02.49%) ++ (7 tiny)
├───5.24 MB (19.46%) ── runtime
├───5.16 MB (19.18%) -- zones
│   ├──2.47 MB (09.16%) -- strings
│   │  ├──1.94 MB (07.22%) -- normal
│   │  │  ├──1.44 MB (05.33%) ── malloc-heap
│   │  │  └──0.51 MB (01.89%) ── gc-heap
│   │  ├──0.42 MB (01.54%) ── short/gc-heap
│   │  └──0.11 MB (00.40%) ++ notable
│   ├──1.88 MB (06.98%) ── unused-gc-things
│   ├──0.42 MB (01.56%) ── type-objects/gc-heap
│   └──0.40 MB (01.48%) ++ (5 tiny)
└───0.27 MB (00.99%) ++ gc-heap

220 (100.0%) -- js-main-runtime-compartments
├──207 (94.09%) ++ system
└───13 (05.91%) -- user
    ├───8 (03.64%) ++ (8 tiny)
    └───5 (02.27%) ── [Expanded Principal] [5]

14.23 MB (100.0%) -- js-main-runtime-gc-heap-committed
├──12.35 MB (86.79%) -- used
│  ├──12.01 MB (84.41%) ── gc-things
│  ├───0.27 MB (01.87%) ── chunk-admin
│  └───0.07 MB (00.51%) ── arena-admin
└───1.88 MB (13.21%) -- unused
    ├──1.88 MB (13.21%) ── gc-things
    └──0.00 MB (00.00%) ++ (2 tiny)

0 (100.0%) -- low-memory-events
├──0 (100.0%) ── physical
└──0 (100.0%) ── virtual

65 (100.0%) -- message-manager
└──65 (100.0%) -- referent
   ├──39 (60.00%) -- parent-process-manager
   │  ├──39 (60.00%) ── strong
   │  └───0 (00.00%) ++ weak
   ├──21 (32.31%) -- global-manager
   │  ├──21 (32.31%) ── strong
   │  └───0 (00.00%) ++ weak
   └───5 (07.69%) -- child-process-manager
       ├──5 (07.69%) ── strong
       └──0 (00.00%) ++ weak

555 (100.0%) -- observer-service
└──555 (100.0%) -- referent
   ├──403 (72.61%) ── strong
   └──152 (27.39%) -- weak
      ├──150 (27.03%) ── alive
      └────2 (00.36%) ── dead

385 (100.0%) -- preference-service
└──385 (100.0%) -- referent
   ├──319 (82.86%) ── strong
   └───66 (17.14%) -- weak
       ├──66 (17.14%) ── alive
       └───0 (00.00%) ── dead

4.20 MB (100.0%) -- window-objects
├──2.33 MB (55.37%) -- layout
│  ├──1.33 MB (31.59%) ── style-sets
│  ├──0.56 MB (13.24%) ── pres-shell
│  ├──0.19 MB (04.62%) ── frames
│  ├──0.11 MB (02.63%) ── style-contexts
│  ├──0.08 MB (02.02%) ── rule-nodes
│  └──0.05 MB (01.27%) ++ (3 tiny)
├──1.14 MB (27.13%) ── style-sheets
├──0.73 MB (17.47%) -- dom
│  ├──0.49 MB (11.73%) ── element-nodes
│  ├──0.18 MB (04.23%) ── other
│  ├──0.05 MB (01.17%) ── text-nodes
│  └──0.01 MB (00.34%) ++ (4 tiny)
└──0.00 MB (00.03%) ── property-tables
</pre>Added preformat tags <nowiki><pre>report text</pre> J99
  0.00 MB ── canvas-2d-pixels
  0.00 MB ── gfx-d2d-surface-cache
  0.00 MB ── gfx-d2d-surface-vram
  0.00 MB ── gfx-d2d-vram-draw-target
  0.00 MB ── gfx-d2d-vram-source-surface
  0.00 MB ── gfx-surface-image
  0.24 MB ── gfx-surface-win32
  0.00 MB ── gfx-textures
        0 ── ghost-windows
  0.00 MB ── gpu-committed
  0.00 MB ── gpu-dedicated
  0.00 MB ── gpu-shared
 50.94 MB ── heap-allocated
 57.76 MB ── heap-committed
   13.18% ── heap-overhead-ratio
        0 ── host-object-urls
  0.02 MB ── images-content-used-uncompressed
 17.00 MB ── js-main-runtime-gc-heap
  0.26 MB ── js-main-runtime-temporary-peak
        0 ── low-commit-space-events
141.61 MB ── private
148.11 MB ── resident
 17.22 MB ── storage-sqlite
442.14 MB ── vsize</nowiki>

Okulungisiwe ngu cor-el

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I do not see anything striking me as odd about that memory report. Other than how little memory Firefox is using.

Okulungisiwe ngu John99

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Would it be beneficial to do further memory reports/comparisons? I notice that about:memory has a "load and diff" feature.

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The Skype plugin has sometimes in the past been associated with problems. I notice you have that but it was shown as disabled when you posted and you have said you tried with all plugins disabled.

For the moment let's assume something is going wrong as you close down and that is the main problem. We could try deleting some possibly duplicated files but the easiest thing to try for now is creating and using a new profile.

Give the profile a short sensible name maybe Fx2014. Use the default location suggested by Firefox, and do NOT delete or rename the profile (at least not without taking forum advice).

When closing Firefox always try to use the proper menu item from the Firefox Button.

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At last... some progress (I hope). As thorough a test of the new profile as I could manage (everything but seeing whether or not Chrome could import it) suggests that the new profile has no problems. No difficulty closing, no problems creating /backing up bookmarks... so far, so good.

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Glad to hear it seems to be ok again.

OK so it probably was something wrong in the original profile.

If the problem was just the duplicated sessionstore files that should be relatively easy to fix.

Did you use the standard create new profile method or did you use the Firefox Reset method ?

You mention bookmarks and so possibly you used the Firefox Reset method, if so you may need to re install Firefox Extensions probably something you do not need help with.

If you used the standard method you may need help in transferring bookmarks etc or repairing the old profile so please post back to say what you did and if you need any more help.

See also

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I used the standard method of creating a new profile. That is to say, I just followed the setup instructions in the profile manager. If you can offer any advice for either transferring bookmarks or repairing the old profile, it would be much appreciated.

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I already included a couple of links in my last post.

Deleting duplicated session restore files may have been enough to get the old profile working.

If you carry on using the new profile you will at the very least presumably want the bookmarks transferred. Maybe you have already managed that using sync. If not then

  1. Save any new bookmarks created in the new profile by exporting them as HTML.
    This type append i.e. Tack-on to the end. They do not overwrite existing bookmarks when imported.
    See Export Firefox bookmarks to an HTML file to back up or transfer bookmarks
  2. (With Firefox closed.) Then rename the places.sqlite database file within the new profile,
  3. And copy over the old places.sqlite file from the previous profile.
  4. The new profile now has Bookmarks & History from the old profile.
  5. (With Firefox open.) Update them by importing the HTML bookmarks, and working within the Bookmarks Library manually drop and drag as required.
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I hate to have to say it, but I'm right back where I started. Imported the places.sqlite file to the new profile and thought I was back in business, but after a few days of having that same "process will not end and the CPU jumps" problem occur intermittently I'm back to having it every time I close out Firefox.

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Hi, I'd like to know where you find "session restore files". I would like to be able to clear all my past History, but am afraid doing so would also eliminate any record of my currently opened tabs & windows, since apparently FF doesn't show the restored tabs & windows in the the current History, after opening them (why not? most other browsers do, and it would sure make it easier deleting all the history before the present opening & restoring of previous session).....

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Hi StevenCee, would you mind starting a new question? This thread is about a different problem and I want to make sure both you and the original poster get specific advice that doesn't get muddled up.

You can start a new question at the following link:

For a desktop browser (Windows, Mac, Linux): https://support.mozilla.org/questions/new/desktop/privacy-and-security

Scroll down past the suggestions to continue with the form (I think it has 3 different screens).

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Hi Obscurebookwyrm, do you recall installing any new extensions or making any settings changes in your new profile over the past several days? Just wondering whether something along those lines could be undone to easily resolve this problem.

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If you do not have other changes to look at.

One change worth thinking about is the fact that the places.sqlite was imported as you put it. I am wondering if that could be corrupt and causing some of the problems

  1. Export your bookmarks as HTML and as a .json backup
    • The HTML at least gives you a file containing bookmark information. That could be useful either to re-import at some stage, or just to open directly with Firefox as a substitute bookmarks list
    • The .json backup is the standard Firefox type. It is only of use when restored.
  2. Make an attempt to check and repair the database.
    • Download install and run the addon Places Maintenance
    • From https://addons.mozilla.org/firefox/addon/places-maintenance/
    • Note it is capable of generating a short report. That is simple text and probably worth copying and pasting into your next reply
    • If it apparently made changes, it may be worth repeating the backup and export steps above.
  3. Move the places.sqlite and the bookmarksbackups
  4. Keep them safe somewhere, anywhere outside of Firefox program or profile paths.

ALTERNATIVE
In fact you may wish to check out this possibility instead by creating a new profile and overwriting the bookmarksbackups folder and places.sqlite with copies from the problem profile (the original profile or the current profile). If that produces problems immediately or after a few restarts it would indicate places.sqlite &/or the bookmarks are causing problems.

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So, after another week or two of fiddling, here's what I've got: creating a new profile and moving in the old places.sqlite does, indeed, reproduce the problem. (Including the fact that any .json backups created are 0 bytes in size. I am, however, able to create .html bookmark backups.) Running Places Maintenance does not appear to have had any beneficial effect, but I will create another post shortly that will include copies I made to the Places Maintenance 'log' data.

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Here are the results of my original Places Maintenance Check:

> Integrity check + The database is sane > Coherence check + The database is coherent > Statistics Database size is 194560 KiB user_version is 23 page_size is 32768 cache_size is -2048 journal_mode is wal synchronous is 1 History can store a maximum of 102102 unique pages Table moz_places has 178893 records Table moz_historyvisits has 4250 records Table moz_inputhistory has 57 records Table moz_bookmarks has 444619 records Table moz_bookmarks_roots has 5 records Table moz_keywords has 4 records Table sqlite_sequence has 1 records Table moz_favicons has 14897 records Table moz_annos has 19290 records Table moz_anno_attributes has 14 records Table moz_items_annos has 41054 records Table sqlite_stat1 has 15 records Table moz_hosts has 28735 records Index sqlite_autoindex_moz_inputhistory_1 Index sqlite_autoindex_moz_bookmarks_roots_1 Index sqlite_autoindex_moz_keywords_1 Index sqlite_autoindex_moz_favicons_1 Index sqlite_autoindex_moz_anno_attributes_1 Index sqlite_autoindex_moz_hosts_1 Index moz_places_faviconindex Index moz_places_hostindex Index moz_places_visitcount Index moz_places_frecencyindex Index moz_places_lastvisitdateindex Index moz_historyvisits_placedateindex Index moz_historyvisits_fromindex Index moz_historyvisits_dateindex Index moz_bookmarks_itemindex Index moz_bookmarks_parentindex Index moz_bookmarks_itemlastmodifiedindex Index moz_places_url_uniqueindex Index moz_places_guid_uniqueindex Index moz_bookmarks_guid_uniqueindex Index moz_annos_placeattributeindex Index moz_items_annos_itemattributeindex Index moz_favicons_guid_uniqueindex

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Here is the 'log' entry generated after running the Rebuild Indices, Expire, and Vacuum options:

> Reindex + The database has been reindexed > Orphans expiration + Database cleaned up > Vacuum Initial database size is 194560 KiB + The database has been vacuumed Final database size is 194560 KiB

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Update: the problem seems to have become intermittent rather than happening every time I run Firefox, so using Places Maintenance may have had some good results after all.

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Try Firefox in safe mode and with all plugins disabled does that prevent the intermittent problems ?

I see you have multiple video related addons. Do you only notice problems when video is in use ?

What happens at present when you try to make the Firefox backups of bookmarks ? Does it now generate the .json backups ok ?

(You mentioned that problem in your first post. IIRC other have reported similar issues, but I do not recall the cause of this issue being properly identified and resolved.)