Mac mini M2 (2023) keeps disconnecting the monitor on USB-C adaptor

Have tried two different USB-C to HDMI adaptors and setting display sleep options, however sometimes I find that the USB-C attached display disconnects even when I'm using both screens actively. Restarting the Mac mini brings the second screen back again.

I have nothing else connected to USB-C that could be affecting this, but have spotted multiple posts on this issue within the Community but no fix from Apple as yet.

Note both monitors and cables worked perfectly on previous MacMini (Intel) and both screens and cables are less than 2 yrs old. Have swapped screens around, but it's always the one connected to USB-C that appears to disconnect at random times, or, if the Mac goes to sleep, the displays swap around - which makes me think the USB-C device has gone to sleep and recovered whilst the Mac was asleep. Really frustrating, as everything else about the MacMini M2 seems to be perfect !