Scott bought an M1 Mac Mini. Loves it. But when his computer wakes up from sleep mode, the video is "snowy." Leo says there's a Reddit discussion that points to this being a known issue. He suggests checking the HDMI cable. Trying another cable could eliminate the easy fix. Leo likes to get his HDMI cables from MonoPrice. But it may be an issue with the M1 mac's GPU. You can turn the monitor on and off. That's a workaround. But Leo thinks it's a handshake issue, and it's something that Apple will need to address in a future update. More details here.