I have connected an LED TV to my CCTV DVR through an HDMI cable and the picture quality is very good, but it is causing a problem. Whenever any electric switch is turned on or off, the picture goes for few seconds and then comes back again.
After a few days the HDMI port is fried and also the DVR is burnt. I changed the HDMI cable and put in a new DVR; the same happened: after a few days the DVR is burnt again, and this time the TFT connected to the VGA port has also gone (the card burnt).
Any ideas on what could be causing the problem or how it could be fixed?