Interesting finding! In another post, I read someobody had 5200 MHz memory modules and when they exchanged them for 5600, all went well. I remember to have ordered one of the modules indicated on Framework’s site, but when I checked with hwinfo, it showed 5200. After a bit more of reseach on the specific product number, I discovered Crucial had problems with some 5200 MHz modules and were offering free under-warranty exchange to customers who had them. The numbers on mine matched those recalled. The modules I had were not the modules I ordered - THEY WERE MOST LIKELY REPLACED IN THE BOX, which read 5600, while the modules had the numbers for 5200 MHz sticks. Of course, the issue may be down to the speed and not to a fault in the modules themselves…
I initiated a replacement with Amazon, hoping this would be the solution. Sharing here as it may well be the culprit. Will report back when I get/install the new modules (5600 Mhz, fingers crossed).