2021 iMac no sound after hard reboot

Yesterday my 2021 iMac would not wake up. checked the breaker box and the power outlet. All were good. Plugged another device into the power outlet and surge protector and it worked. After unplugging the iMac and restarting it, it looked to be back up and running yet when I tried playing something on YouTube, I got no sound. Checked my system settings/ sound. play sound effects thru iMac speakers. alert volume maxed out. play sound on startup-check. play user interface sound effects-check. play feedback when volume is changed-check. After I do a re-start and then go to system settings and click on the alert sound button to hear anything, I hear the alert but only once, then it goes silent.

This is the first time my iMac has ever done this. the no sound and the hard reboot. Any suggestions on how to fix this? thanks