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CableCARD signal strength drop

Frequent Visitor

CableCARD signal strength drop

Last Thursday was the last time cable card was working. Sometime on Friday, the signal strength and quality bottomed out. Since then we're only getting signal strengths in the low 40% range. As a result, our HomerunHD Prime cannot get any channels. Nothing has changed in the house. What else could cause the signal strength to drop so significantly (we were in the 90s on Thursday)?


Card Authentication          success

Card OOB Lock                weak

Card Validation                 success


Signal Strength                41% (-35.8 dBmV)

Signal Quality                  46% (17.0 dB )

Gold Problem Solver

Re: CableCARD signal strength drop

CableCards only authorize and decrypt channels. They don't affect signal strength or quality. This is not likely to be a "CableCard" problem.


Your readings indicate that the signal for the channel you are trying to watch is too weak and/or has too much noise. This might be because of a problem at Comcast (check, 1-800-Comcast voice response, or the "My Account" app) but is most likely due to a poor connection between the HDHomeRun and Comcast's network.

Troubleshoot by checking all connectors for corrosion and tightness, and by looking for damaged coax cable. Running the cable through a surge protector, a defective splitter, or too many splitters can cause signal problems as well. If there is an amplifier in the line make sure it's getting power.

If you can't find the problem, call them at the phone number on your bill or 1-800-Comcast, or chat with them using the TV Support option at If they can't fix the problem remotely, insist they send a tech out to identify the cause and correct it.

If the tech finds bad coax, splitters, amplifiers, or connections in your home (even if Comcast originally supplied them) you'll probably have to pay for the visit unless you have or sign up for their Service Protection Plan (, about $6/mo) and keep it for at least 60 days. If the trouble is due to anything outside your home, you shouldn't be charged.

For additional information please see Pixelation, video and audio dropouts, One Moment Please S0a00 messages.

Frequent Visitor

Re: CableCARD signal strength drop

The tech tested the line post Comcast-installed splitter - the values were all great. After going back and forth with SiliconDust, they decided to RMA the HDHomeRun Prime. A new one is being sent.