If the problem is more towards a software one, I would think about refresh rate / refresh requests, hence a software issue.
sudo rpi-update pulls/6417" - throws error on incorrect tar/zip file
this suggests a corrupted download of the tar file... maybe achieving a correct one and installing it could exclude/confirm a driver problem.
also, hardware acceleration off could be the cause, involving more cpu power... but would address this later, after the driver update is successful.
I would focus on this issue getting fixed, first.
sudo rpi-update pulls/6417" - throws error on incorrect tar/zip file
this suggests a corrupted download of the tar file... maybe achieving a correct one and installing it could exclude/confirm a driver problem.
also, hardware acceleration off could be the cause, involving more cpu power... but would address this later, after the driver update is successful.
I would focus on this issue getting fixed, first.
