Volume on TV goes up or down by itself

Roku: Ultra RT

TV:  Old Olevia 46 inch

Problem:  Sound would go up or down by itself, no ryhme or reason to it, completely random.  Switching out of an application would fix the issue temporarily, it mostly happened with the Xfinity App, but I believe it also happened with other applications.

Solution:  I tried several different settings but turning on the leveling function seems to have worked, I've been watching TV this morning for about 3 hrs and it hasn't reverted to the old issue.  Hopefully this is a permanent fix since I like the Roku device and software.