If you using the “EVF-DC1”, then you may have the wrong device. I use the “EVF-DC2” with my M3. I think the “DC1” is designed for Powershot Series, not the M Series.
The DC1 is what was available when the M3 was released. The DC2 is the recommended accessory for the M6 Mk II
The DC2 is recommended, in part, because Canon no longer sell the DC1. Which I feel is a shame because I use the articulation of the DC1 often.
I'm aware that it Might be a communication issue, but there is no reason it should be. And I am trying to find out if it is definitely insolvable or if it is a bug in my particular camera.
Take a look at this link. Tap the “What is in the box” button.
This does not answer my question. That they include the currently manufactured evf instead of the no longer manufactured evf says nothing to compatibility.
And I just discovered a VF display menu which solves the problem.
09/26/2023: New firmware updates are available.
08/18/2023: Canon EOS R5 C training series is released.
07/31/2023: New firmware updates are available.
05/31/2023: New firmware updates are available.
05/18/2023: New firmware updates are available.
03/30/2023: New firmware updates are available.