Dead dimmer?

Hi all, one of my dimmer’s (L5508D1A) is having a moment it seems. For a while one of the channels has been flicking off for between a few milliseconds up to 1 or 2 seconds a few times per night, but now nothing works at all. Only the first channel physical button works (ie lights up) - the rest do not.
The unit and cbus lights are on (on the dimmer) as usual but I guess that doesn’t really mean much? Do I just need to replace it or is there anything else I can check? I’ve tried power cycling it.
Thanks!

 

Did you remove the cbus cables as well as turning 240 volt off sometimes this will fix that problem if that dose not work dimmer needs replacing

 

Will bear that in mind for next time thanks - weirdly it fixed itself a short while after the power cycle (maybe 15 mins?). Was convinced it was dead.