I believe its something to do with customisation set ups, but also the firmware version itself, I never had any problems within Ver 1.4, the odd lockup with 1.5 but more with 1.5.1.
Define your use of "widespread," and back it up with something other than "A lot of posts."
If you haven’t been living under a rock since the R5 was released I’d say you already know how widespread this is. The definition of widespread is when Canon releases a firmware to fix it, and use the phrase “in rare cases”.
I don't know what threshold Canon has for responding with a FW update, but, you are right, they took the complaints seriously enough to target the freezing/lockups with a minor update.
What is the possible relationship with the memory card with this? I just got 2 R5, so far one has done it 3 times in my first outing. I had my 200-400 f.4 with built in 1.4 extender adapted to my camera, wasn't until later I was in Electronic 1st curtain shutter. it would do it at the beginning of my burst, then I shut it down and started and it was fine. But again kept reoccurring. I am still in testing phase and haven't tried all my EF lenses yet to see if this happens and it's only been on one body so far. I should add I was writing to a new prograde CF express 256 type B card.
A lot of people have tried to tie it to memory cards, but there is no evidence that there is any relationship. Nor is there any evidence it is related to lenses. In fact, there is no simple or even complex cause and effect relationship, despite what some people think. Some individual cameras seem more prone to it than others. If you have a new camera that does it regularly, I'd suggest a return. At least one forum participant was having issues almost every time they shot. I have had intermittent issues with two R5s (one is my wife's) and one R3. Recent firmware updates seem to have made some improvement, but have not fixed the issue.
