Audio syncing issue with H.264 exports

Hi, I'm making some talking head YouTube videos in Premiere. Mostly talking head videos 10-20 mins long.

The source footage is recording on a blackmagic ATEM Mini Extreame ISO, so it's H.264 1080P 29.97 fps at around 25 mbit/sec.

All the audio and video is perfectly synced in my timeline and plays back fine. When I export with the high bit rate H.264 profile in Premiere (with match settings), the resulting file starts in sync but gets out of audio sync by the end of the file when played back on quicktime. However, the same output file stays in sync played through VLC.

If I output the same sequence with  med bit rate h.264 the video stays in sync when played in Quicktime and VLC.

Arguably, the problem is with Quicktime since the file plays in VLC, but Quicktime is so popular I hesitate to use a file that doesn't play well in it. Any tips or advice?

Is my problem with my source footage (do I need to transcode to an intermediate format)? Some alternative export settings? I'm pretty much a newby, so any tips are greatly apprecaited.

Thanks!

-Jason