I have been having issues after rendering either with GPU or software processing via Media Encoder. Some clips appear at double speed, and sometimes, red frames also appear. To solve it I have had to unistall and reinstall Premiere and Encoder, but after some weeks, the issue starts again. This is on multicam projects. I am using Premiere Pro CC v12.1.2

This issue does not happen when I export directly in Premiere (without Media Encoder) and as a software processed export.

But I need to export via Media Encoder and GPU because it is quicker and also because I can export several projects one after the other overnight.