I was working on rendering out a new 30-minute DJ promo with electro house using Ableton Live (more about that project later), and this really strange problem happened over and over. About 13 minutes into the mix the sound just disappeared for 20 seconds in the rendered version — this didn’t happen when playing back the same part in Ableton Live.
I tried all kinds of tricks, restarted the system, upgraded to 6.0.3 in case this was a known bug, re-warped the track, moved the problematic audio snippet to another track, even joined together the parts in case the clips stacked next to each other didn’t work. Nada, same problem.
My last attempt was the surgery tactic, as this problem happened when one track ended and the other started, I cut out four bars of the starting sound as a timeline operation. This fixed it. So something odd was recorded into the actual project at that point. I double-checked all the envelopes in case the mixer was off, or something else, but they all looked fine. So it was something internal.
That, or the combination of one track ending and the other starting caused a problem somewhere in the sound chain — it could have even been the Izotope Ozone plugin that was running in the background as a mastering chain. Anyway, as I run out of time, the surgery trick was the best I could do.
Lesson learned, learn your tools inside out so you could do all kinds of strange and quick operations to get results out in case mysterious problems appear.