I’ve also hit this issue- and foolish me didn’t realise that the modules are at the bottom of the machine so have had two failed attempts at fixing this… I’ve unplugged and plugged in the joining cable at the dryer module and washer module end a few times each and will update if the problem has stopped. Thanks for the hints.
I’ve also cleaned out the crud that accumulates at the edge of the drum inside- had to remove the door seal but got two handfuls of muck out that I think have been causing a squeak. I suspect this is common with washer dryers.