When you say "OSC" camera...is it a CCD or CMOS sensor?
Spikes are a hallmark of CMOS readout architecture...( simply put...the nature of the beast....I gave a talk on this
at the CWAS/Astrofest a number of years ago )
If it's a CCD...bugger...much harder to nail the cause down...but I'd be cleaning all optics that close to the sensor for a start
