DVR, Cable TV.
The easiest place to start is to temporarily disconnect the CATV Coax cable from the DVR. If that stops the hum that means a difference of potential, voltage, exists between the CATV provider's shield of the coax cable and the safety equipment grounding conductor at the wall receptacle.
A digital ground loop isolator like the Jensen VRD 1FF will stop the hum if it is caused by the CATV company's coax cable. The isolator will not correct the grounding problem though.
Disconnect the CATV coax cable from the DVR. If that stops the ground loop hum post back your finding.
Jim
The easiest place to start is to temporarily disconnect the CATV Coax cable from the DVR. If that stops the hum that means a difference of potential, voltage, exists between the CATV provider's shield of the coax cable and the safety equipment grounding conductor at the wall receptacle.
A digital ground loop isolator like the Jensen VRD 1FF will stop the hum if it is caused by the CATV company's coax cable. The isolator will not correct the grounding problem though.
Disconnect the CATV coax cable from the DVR. If that stops the ground loop hum post back your finding.
Jim