Rolling faint horizontal lines on Public View Monitors HELP!

I installed 6 dedicated micros ds2 DVR's with 5 pvm's 2 are fine 3 have faint rolling horizontal lines our client is not happy ,which means guys as we all know we are not happy and I need to get this solved. but I cant do it alone so I'm seeking council I've tried different power sources thought maybe it could of been feed back from ballast from florescent lights but same thing, ground loop isolator ,and all basic troubleshooting I was wonder if i should try a dc blocker i don't know ? please help thanks.

sorry for typos just pulled a 16 hr graveyard shift and i am really tired I'm going to sleep now thanks again guys.

sounds like ground loops or possibly noise getting into the cable (ie to close to power cables etc).

I would for sure check out the ground loop problem. Make sure all racks and equipment are grounded. Also try to check each unit one at a time are you using isolated power supplies for cameras?

I think you mentioned floresent lighting? I have had to change the refresh rate on computer monitors from 60 to 75 as they were somehow sync with the lights. It made the monitor look like it had problems but really it was the light in combo with the monitor. I guess a good example would be watch a tv news program when the tv camera shows a tv in a house you usually don't see a picture just a horizontal line rolliing.

Refresh rate that makes sense i will try tonight were using vizio lcds should have adjustment ill google it let u know how it goes thanks for ur time .