Funkwerk/Filser have just issued a
service letter that paves the way for these units to be put back into full service again.
Reading the last paragraph of the letter it does appear to confirm that there are problems with the certification standard.
Presumably some EASA ADs to follow.
(I did experience some difficulty in downloading the letter and had to follow a link to
here, right click and "save as" before opening the PDF file).