There is no Bash Button...
I have never heard the expression before - but in the days of valve TV sets a misbehaving television could sometimes be encouraged to begin working properly by smashing hard on the case - to fix a poor connection - I've seen it work - I've used the technique of sudden applied force as a diagnostic aid on electrical equipment where a poor connection was suspected.
The bash button is an expression that very probably means to hit the set with mild force to see what happens - bashing is just as likely to cause a fault as it is to fix one.
You will not find a Bash button on your set's remote control - just at the end of your arm.
Good luck...
Basher
October 2014