Default audio changes on its own when I start up a game or youtube vid

I just recently built my own computer and everything has been working great so far besides one thing. I have my default audio set to my speakers but whenever I load up any game on steam or even watch a youtube video the sound changes to come out of my monitor speakers as well as making the monitor speakers my new default audio. If I quit the game go into control panel, change it back, and load up the game again it will work fine and come out of my speakers and continue to work fine until I shut down my computer and start it back up.

I hope I explained that properly. I don't know why it does this but its really annoying, any help would be greatly appreciated.

HammerHead said:

Depending on how you use them you could disable the monitor speakers. Also check in the game you are referring to. You could possibly set the sound out to another source.

I thought it was the game at first as well but its done it with every game I've played (3 games) but with that said disabling the monitor speakers worked. I never even thought to right click to see there was a way to disable them.

(PS)
I noticed since my OP that it seems to happen whenever I go into full screen but either way its no longer an issue.

Thank you for your help!