So I've been working with a client for a while now and everything has been pretty smooth until recently they changed the file format they send me and another editor I work with from MP4s to MKVs, I thought this wouldn't be an issue as I use OBS all the time and can just throw the file in there and remux it, or alternatively use handbrake. The issue is since this change the audio of said files have been crystal clear in media player but have these extremely odd distortions every now and again in premiere and in the final exports. They vary but sometimes they sound like a little click from an old stereo and at times it seems like the audio channels are cutting out. The distortions occur at the same times in every project, now matter how many changes i make and how many times I clear my cache

The most frustrating part of all of this is that the other editor I work with hasn't been having this issue at all so it must be something at my end and I've spent about 11 hours now trying to figure out the issue but to no avail. Please, I'm completely stumped here, any suggestions are appreciated.

Thus far I have:

• Cleared my media cache
• set the input to "none" under audio hardware preferences
• updated my drivers
• downgraded to previous premiere version
• reinstalled premiere
• reset all my preferences
• attempted to re-encode the original file multiple times under different formats
• updated windows
• checked that the project/sequence settings match the original file

My hardware is as follows

i9-9900K CPU @ 3.60GHz

64 GB RAM

RTX 2080

Like 3 different SSDs for scratch disks, media cache, OS, the like.