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Some videos in Firefox play on Output 3 in my system audio instead of Outputs 1/2 like all other system audio and browsers

  • 1 reply
  • 1 has this problem
  • 19 views
  • Last reply by Rob Gray

Rob Gray
Rob Gray
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I use an audio interface that has four outputs. The standard outputs are 1/2 (Stereo outs). All my system audio runs through these. There are also unused outputs 3 and 4.

For some reason, some videos on Facebook and Instagram come out of output 3 in Firefox.

When I turn off my audio interface and use the "Built-In" Speakers on my Mac Pro, I hear no sound at all, which leads me to suspect it's erroneously being sent to "Output 3" even when I don't have the audio interface involved at all, making it seem like a Firefox issue.

Most videos on Firefox are fine, but it's just some of the videos on Facebook and Instagram.

The same videos come out of outputs 1 and 2 in Safari just fine.

I tried all the usual stuff- Safe Mode, Disabling Extensions and Plugins, Disabling Add-Ons, Disabling Flash, Disabling the "Block malicious" setting in Flash, Disabling hardware acceleration, Refreshing Firefox, and nothing fixes this.

Why is Firefox doing this?

I use an audio interface that has four outputs. The standard outputs are 1/2 (Stereo outs). All my system audio runs through these. There are also unused outputs 3 and 4. For some reason, some videos on Facebook and Instagram come out of output 3 in Firefox. When I turn off my audio interface and use the "Built-In" Speakers on my Mac Pro, I hear no sound at all, which leads me to suspect it's erroneously being sent to "Output 3" even when I don't have the audio interface involved at all, making it seem like a Firefox issue. Most videos on Firefox are fine, but it's just some of the videos on Facebook and Instagram. The same videos come out of outputs 1 and 2 in Safari just fine. I tried all the usual stuff- Safe Mode, Disabling Extensions and Plugins, Disabling Add-Ons, Disabling Flash, Disabling the "Block malicious" setting in Flash, Disabling hardware acceleration, Refreshing Firefox, and ''nothing'' fixes this. Why is Firefox doing this?

All Replies (1)

Rob Gray
Rob Gray Question owner
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Any thoughts? I contacted the manufacturer of the audio interface and they said it’s something that Firefox is doing causing the audio to come out of output 3.

I’ve come to rely on the Browser Syncing in Firefox so it’s very frustrating to have to use a second browser to watch videos.

Modified by Rob Gray