Mac Mini: No sound except for startup chime I have a Mac Mini (mid 2010) and out of nowhere the sound has completely stopped working, the only exception to this is the startup chime when turning on the machine.

I have already checked to see if I just muted the sound, that the internal speakers are selected in system preferences, reset the PRAM, restarted the computer, and wiggled a jack inside of the headphone jack hole.

I have no idea what is going on with the sound! I know the speakers are not broken because the startup chime works, also I've tried using external speakers but those don't solve anything either.

Any thoughts?
Try this
https://apple.stackexchange.com/a/54800/210364

I had the same problem, and these steps helped:

Reboot your mac holding Command + Option + P + R until you hear at least two startup chimes.