Roamio Pro - comcast certain hd channel weak signal

For some reason a few of my hd channel for comcast have weak signal while others like 95+? E.g. cartoon network has 0 &some time 65 so I get v52 error while sd no issue. I tried to connect without the splitter still same issue, could it bee the cable line issue?

Roamio Pro - comcast certain hd channel weak signal