Audio missing or distorted in renders, randomly

Hello fellows

I have a mystery to solve:
manually syncing a small sequence of clips for dailies recently, after rendering I discovered that the audio was bad for some of the clips, but not for others. and the weird thing is, after trying again, the same audio problems appeared but for different clips this time. some clips had no audio in the output and some had audio that was peaking across all channels with heavy distortion- and then a few came out fine.

the strange thing is different clips were effected upon re rendering the same sequence with no changes a second time.

some strange voodoo going on here

I ultimately exported an xml to premier to workaround this but figured I should let it be known.

I was rendering to Prores from Alexa footage and .wav files from a SD702t
1080 with AAC/ variable bit rate/ best/same as source/16/single


I tried pcm and various other settings, but couldn't seem to figure out why this audio render problem was occurring.

unfortunately later I discovered many other clips that I had rendered out for dailies also had this audio problem, but it was too late so we sunk up in the edit.

does resolve 12 have major issues under the hood- what could be going on here?

I'm using a Mac Pro 2013, ssd drives

I guess one of my issues was that I synced in the edit tab.

this could explain the missing audio,

but it doesn't explain the corrupted audio outputs

I'm having a similar issues syncing audio in DR version 14. Did you ever come up with a successful workflow?

I can playback the synced audio in DaVinci , but when I the output dailies the audio tracks are empty.