Those symptoms usually happen when the signal for the channel you are trying to watch is too weak or has too much noise, most likely due to a poor connection between your home 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 use one of the options on https://www.xfinity.com/support/contact-us/. 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 their Service Protection Plan (https://www.xfinity.com/support/articles/service-protection-plan, closed to customers that don't already have it). If the trouble is due to a faulty Comcast cable box/DVR/digital adapter or anything outside your home, you shouldn't be charged.
Greetings, Ashmanahan! I appreciate you taking the time to reach out to us here on the forums. I hope you are having an amazing day. I apologize to hear you are having issues with these two channels in regards to video and audio problems. That's certainly frustrating. If what BruceW has provided you do not yield any results, feel free to send me a PM with your first and last name so I may further assist you.
To send a private message, please click my name "ComcastMichael" then select "Send a Message" on the right side.
Hello, Ashmanahan. I have not heard back from you. If you still need assistance, please feel free to start a new public thread.