I might not be able to help much but, when it last functioned as a blowback; how well was it cycling? Was it slow? And when was it last cleaned? Daft question about how clean, but it's surprising how many people say something has stopped working and then say it's never/rarely been cleaned.
And yes, i wouldn't fancy stripping one either.
I've sold a few of these pistols but no one has reported any problems.