I have some content (Criterion) that has LPCM1.0 Audio track that I'm trying to put in to an H265 MP4. The problem is playing back the MP4, all the audio is on the left side (PowerDVD17, VLC, Plex). There is no mono setting for the transcode so I just left it at Surround 5.1 (384kbps) expecting the audio would come out center channel or on all channels but no such luck. It doesn't play that way from the disk (PowerDVD17).
Tried AAC, AC3 and 5.1 and stereo, audio is always in the left channel only. Transcoding with Handbrake now, which does have a mono setting, just takes a couple hours and there's 25 of these movies! The second movie has the same issue apparently.