I've been using UI2 for about 4 or 5 months now, it's awesome, thanks for programming this and making it available.
One odd thing I noticed, recently (within the last few weeks) I upgraded
Blue Iris to latest 4.0.9.14 x64, and Firefox to latest 38.0.5, and UI2 to latest v0.8.2. Prior to these upgrades, when I clicked on a particular camera, the audio would start streaming immediately, and was relatively in sync with the video. Now when I click on a particular camera, I hear a brief burst of near-real-time audio, then 12 or 13 seconds of silence, and then the audio starts up again, but now 12 or 13 seconds delayed from the video. This problem was present in Chrome even 5 months ago, but now it happens in Firefox as well, on both PC and Mac. Same problem also in Opera. No audio at all in IE11 or Safari on the Mac, but I don't think that ever worked.
Also, another problem that has cropped up in the last month or so is a flickering of the video feed when using the default JPEG mode. Doesn't happen in Opera on JPEG mode, but does in Firefox 38. Doesn't happen if I enable MJPEG mode in Firefox, but then switching cameras is slower, and that doesn't help the audio issue.
I fired up my old BI 3 system, and got the same problem, so I decided to check and see if it was something that came in with a Firefox update, I had an old Win 7x64 virtual machine with Firefox 31.0 on it, and sure enough, audio works fine. So at some point here Firefox changed something that broke the audio. Any ideas what that might be? Maybe an advanced setting in about:config ? I did a brief stare-and-compare and tried toggling a view settings that were different from Firefox 31 to 38, but they didn't seem to help either problem. Firefox 31 also had a little bit of the flickering, but not nearly as much.