Do I have a ground loop issue?

[rohrt]

Yeah you didn't mention the issue. That would help.

I worked for a communication company for a number of years so I can help explain what a ground loop is. An example with security cameras over a long distance. The camera would be powered at one location and coax ran to a Monitor at another location. The ground for the camera has a different potential then the ground for the monitor and because of this there is a current running now running over the coax cable that can either cause static or scramble the picture. We would fix this with an isolation transformer. This would essentially decouple the grounds. We did the same thing with audio lines. We would get a horrible buzz between two pieces of equipment in different locations. Again we would install a 1:1 isolation transformer used for phone line and resolved the issue.