What is causing picture on one of our 5 tvs to keep intermittently freezing and for various lengths of time?

Watching program and picture freezes but sound continues. Can lost for short period of time or hours. Changing channels sometimes helps sometimes doesn’t. Only tv hooked up to Cisco wireless receiver. Replaced HDMI cord. Put fans in cabinet. Pulled receiver out of cabinet. Nothing has worked and it has become more frequent as time has gone by. Troubleshooting has not resolved the issue. Do I need to get new receiver. This does not happen on any of the other TVs.