Several glitches like that happen to me.
When I go into Google music and I have the headset in, and I go to customize the sound to dance, pop, hip hot etc as soon as I click on it to pick a genre it automatically restarts. It did three times one day in a row. And it does it basically every time now.
The thunderbolt was known for having this issue and it rebooted far less times than my nexus does.
Another glitch I have is that when I'm in a area with bad coverage it starts making a call to a weird number like *228 or something. Very annoying.
Too many glitches for a new phone! I'm waiting for an update for it before I decide to root it. If the update fixes a lot of glitches and does something about the battery I won't need root. My android os awake time is twice as high as my screen on time and recently even the CPU time on it has gone higher than usual.
My android os started going up again for some strange reason. I did a factory reset and it was good for a while.