I've been using Premiere for quite a while (I still have the 2.0 version), but this problem never occured before. I'm running Premiere on Win Vista.
I've been working on a project for a few weeks and eventually I got a version that was more or less final. Thus I tried to render everything a few times (Quicktime H264) but the render never succeeded because of an "API failure". Didn't manage to fix that, so I tried to render in wmv, just to check if it worked.
Well, it worked, but when render finished all the audio tracks had disappeared form the Timeline. I tried to find a solution on the web but couldn't find anything useful. No matters how much I scroll down and/or move the windows, the audio tracks just are not there. And the triky part is that I still can hear the sound when playing the sequence! I tried to add some empty audio tracks and Premiere apparently does it (it records it in the history), but no audio track shows up...