HR23 HD DVR Receiver Purchased from Best Buy

I have a HR23 HD DVR receiver that I purchased from best buy less than a month ago. All indications according to some post and my experience tell me that the hard drive is failing. I get video and audio stutter when viewing from DVR.

I don't get any stutter when viewing live and my signal strength are all in the 90's on both tuners. All connections are solid.

My question is will Best Buy exchange this unit for me. I'm still under the 30 day policy. And should I deactivate this receiver before I take it back? Thanks.