Default Weak Bluetooth Signal

I'm going to go out on a limb and say this is a common problem for the SGS3. Previous to my HM1900 Samsung Bluetooth I had the HM1800. The 1800 worked flawlessly, around 25 feet or so through a wall, turning my head, etc., how a Bluetooth should work. The HM1900, however, is awful in comparison. During work, I keep my phone in my right breast pocket with the headset in my right ear. I stream music while working (in near-perfect 4G) though if I put my arm over my chest, or turn my head, I lose signal. Could it be the headset itself, or is it a possibility that it's a combination of both?

On the phone I have the Otterbox Commuter case, so it isn't that thick. The phone is not rooted and running 4.3. I have attempted at doing a software update, but nothing downloads. Is there somewhere to download a software update for the Bluetooth itself on the phone? Or is this just a lost cause?

I would rather keep the HM1900 just because of how well built it is, I easily ruined my HM1800 within two weeks for it not being as robust.

And another side note! Volume is damned quite on the headset even with everything at full volume. Any volume control fix or app?