This sounds like a weak signal. Check the connections to the cable box, especially the incoming coax, and eliminate any unnecessary splitters.
To check signal strength with a Motorola box, turn off the box with the remote, then within two seconds hit "OK/Select." This will bring up the diagnostics screen. Select "Inband Status" (probably page d04) and look for "SNR" for the tuner(s). This value should be in the mid to upper 30s. You may be able to improve the signal strength by adding a signal amplifier to the incoming cable line.
Message Edited by WarEagle57 on 05-25-2009 09:46 AM