Very, very, very frustrating issue.
I have a cut of a scene where the audio has all mysteriously gone offline (the clips in the timeline have turned red, rather than green). No audio plays back. Yet when I select "Reveal in Project", it finds the associated audio file. That audio file plays fine in the Source Monitor, fully online, waveforms, plays back fine. I can select "Edit Original" in the timeline and the original file will open up in iTunes and play fine. I put the file from the Project window offline and reconnected, yet the clip in the timeline doesn't change at all. It is connected, but doesn't act like it. Checking the timeline clip's properties, it says "Online". But it's not.
The most frustrating thing is that ONE of the shots has online audio that plays back. This is the same audio file as some of the other shots that register as offline!!!!!!!! It's absurd.
Earlier cuts, using the exact same audio files are all online, all work fine.
I have deleted my media cache, went back to an earlier auto-save, no luck. When I double-click the clip in the timeline, it opens a blank audio preview in the Source monitor, no waveforms but it does have my In/Out points. I tried copying the timecode and applying it to the ONLINE version of the file from the Project panel, but the timecode was bizarrely different and didn't match so I can't even use the "Replace with Clip" command. It's insane.
Any insight or help on this issue would be much appreciated. I've already had to go about re-adding clips manually, but hopefully for next time I can have an easier solution...
Just a thought, and it might not apply, but in the Timeline, PrPro relies on the CFA (Conformed Audio), and the PEK (Waveform Display) files.
When on Imports source files with Audio, PrPro needs to Conform and usually Index the files. If that process does not complete, then behavior, similar to what you describe, can occur. This ARTICLE goes into more detail.
A bit same pb happen to me. The cut was OK I close it and a few days after open the project and the sound was in RED. Also all the rush were offline.
My rush were in : AVCHD 1080p - Pixels carrés
Base de temps : 25,00 i/s
My solution is to copy in the same directory the rush (for exemple 00002.MTS become 00002_2.MTS) and to reconnect in Premiere the rush 00002.MTS with 00002_2.MTS. (don't know if I am clear !).
This solves the problem for me.
Rq : if I clear the original file (00002.MTS) an rename the 00002_2.MTS in 00002.MTS the error is back ! Stange !
I have encountered the same issue and it is a huge pain.
Just now I realized that you can select all of your audio, right click and select "Audio Channels." You will notice that "None" is currently selected. Change the setting to which ever channel has the audio (if you are using two channels select one for right one for left--not tested, will probably work). And voila, reconnected.