Issues

No sound output on headphones

Use alsamixer and F6 to select sound card. Mess with mutting/unmutting controls there.

I was expecting the "stereo" output Pipewiere is for headphones but that is not the case. Both speaker and headphones outputs work as the same output, just headphones are muted by default on ALSA level.

Notch in the trackball

My trackball had a little notch making it stick. A bit of "super glue" and sandpaper did the trick.

On first boot screen is blank or only top half of it is working and looks corrupted

Just boot again. Looks like some initialization issue.