Quark is corrupting some document names

[Niggle]

Several times lately my version of Quark has altered the doc name when I've gone to save it, usually the first part being the same, but then turning into a series of random characters, and still saving with this strange new name, even after I've corrected it in the Save-As dialogue box. It has only happened a couple of times but it's a bit unnerving. I'm using 4.11 with SystemX.2.8