K35 Hot Pixels

Hello Arne and Tom

I am seeing lots of hot pixels in the SN2011DH images, with values of 28000 to 49000.  Looked at fits header and temp is -37.66 on most images.  Some at -38.  Exposures at 300 secs.  Some pixels are so hot that they confuse Maxim PT tool.  Do we know what causes these.  I do not remember them in the RR Tau images, nor the KK Oph pics.  Its not always the same pixels, but quite often it is.  Suggestions?  Any known problems?

Gary