So first, I love this program, especially if cutting is involved.
But with 2.7.6 nothing worked here, for example youtube videos. I did a fresh install.
Cutting made visual errors in the endfile, so I deiced to reencode, although there was no warning or something, that it would be required, but even than, the audio was flawed at cut points.
Going back to 2.7.5 and everything just works. To have working "cutpoints" and not have to reencode is what this program makes so good.
Please provide details which would allow to identify the problem: the YouTube ID number and video stream ID of the affected video and the exact steps to reproduce or at least the project file (load the video, perform the cuts, save in copy mode, then File --> Project Script --> Save as project).
A small chance that I might be experiencing something related: https://avidemux.org/smif/index.php/topic,19223.0.html