Placement of Speakers causeing muffled sound?

[GamerZero]

I've been playing some more on my new Nexus 7 and I'm noticing once and a while the sound seems muffled at lower volume levels, its not the static or buzzing noise that some Nexus 7 owners have reported but I'm starting to wonder since I'm gaming while holding the tablet verticaly with both my hands grasping both sides if my hands or fingers themselfs are covering the speakers thus causeing the muffled sound, any other new Nexus 7 owners experiencing this?