Static Sound

After watching TV for a certain time period, a static sound happens.  When I switch the channel and switch back to what I was watching the static is gone.  It does not happen all the time and it doesn't matter which channel I'm watching.  There is no set time for the static to appear, it just happens when it wants to.  Is there a fix for this?  I should add that Im using Roku as my remote if that matters.