Channels switching in the middle of programs

For weeks I had been having a problem with the Xfinity website streaming network programming on the wrong channels.  That seems to have finally been resolved.  Now programs on the tv are spontaneously switching back and forth.  COMET TV on ch. 183 randomly switches to Dabl which is actually ch. 181.

The channel doesn't change, only the program does.  Imagine trying to watch a movie and then suddenly, you're looking at a cooking show!  Today my neighborhood also experienced our 3rd outage this month.  Why does this stuff keep happening?