Specs:
AE - latest version
i7 7700hq
Gtx 1060 6gb using latest Nvidia Studio Driver (also tried older versions)
16gb RAM
I have a simple project in AE. Its just a static background video (.mxf CBR) with an animated text opacity loop. I'm using 1/4 preview and generally have the .mxf background disabled. The comp is only 1920x1080p.
The main issue is that the audio in the file does not match its file length. The audio is exactly 1hr and is CBR. I've used WAV and AAC (both CBR and VBR). The imported audio is always ~4s shorter than the actual file but is not cut off.
My audio settings for hardware AE and everything else are set to 48khz, the audio files in question are 48khz. The buffer for my interface is set to 1024 which should be more than enough.
The secondary issue is that (I believe because of whatever is interpreting the audio wrong initially) the animation doesn't stay synced to the audio. I even tested to make sure that I had the correct animation length. The audio file is with 100% certainty exactly 60bpm.
To test I made the looped (loopOut()) animation at lengths of 5:29, 6:00, and 6:01. The 5:29 stays synced till about 8min in until there is a noticeable lag and then it goes off. The others don't stay synced (as expected). When exported in various formats with either 29.97 or 30fps I still get the same result and syncing problem.
Possibly related issues: One strange issue is that sometimes during playback my display will flicker and the audio will change pitch and speed, almost like its changing sample rate. Usually then I'll get an 'Unspecified Drawing Error' and 'Unknown exception' or sometimes 'Out of memory, 296k requested' and occasionally the program will crash along with my display driver and I have to restart. On export the audio will also sometimes have skipping sounds (not typical pops and crackles with too low buffer)
Things I've tried: using both my interface's ASIO and MME drivers, using the built in sound card, triple checking the audio rate settings, uninstalling and re-installing AE, having only AE open, using my interface exclusively for AE, updating display drivers (tried both studio and gameready), purging cache
Note: I would try Premiere instead but I'm using CompsFromSpreadsheet to create many different versions.