I have recently experienced pixelation, temporary loss of audio and/or picture with Verizon FiOS which all pointed to signal strength issues.
I called Verizon and here’s the first thing they had me do in order to confirm (or deny) poor signal strength:
1. On your FiOS remote click on Menu
2. Then select Help
3. Go to Self Diagnostics and click start.
This should take less than a minute and if everything is ok all tests should clearly pass and results should be written in green text. If any of them fail then you need to call Verizon for further assistance. Also, note that according to Verizon’s support your signal strength should be 25 db or higher (even though lower db’s might work fine as well).