technical issues with 0.4-m f/3.8 setup

I noticed that the images are very bad, taken with the 0.4-m f/3.8 setup. Problem was that the all stars appears as comets. Very strange. I could not at first immediately pinpoint the cause, after all, nothing had been changed in the installation. I then started by checking the basics, power supplies, etc. The CCD camera is powered by the same 12VDC power supply as all items on the telescope, including the mirror heaters. I then measured the DC voltage at the camera itself while all the consumers were on. I measured only 10.9 VDC there. This is far too little. I then increased the supply voltage to 12.5 VDC at the camera itself. If the anti-dew heaters get a higher voltage is not a problem. Afterwards did a test and the images are OK again. problem solved.