Long-time lurker, first time poster. My MacBook Pro 15inch makes a hollow sounding click/ping noise when I move along the track pad. It's NOT the motion sensor, that noise is more defined and pinpointed. This noise is random, sometimes occurs non-stop for an hour or two at a time every time I move the mouse, but usually occurs at random. Sometimes it also occurs when i have my computer on my lap or tilted and move it from side to side. But again, it is not the normal motion sensor noise. I'm on my third MacBook Pro in less than 30 days. My first one corrupted all my files and my second one pinged like this one. I just need confirmation that this is actually OK and I will get a good MacBook and the money will be well spent. I think most of my issues stem from the fact that I'm new to Mac and just don't know what is normal. Thank you so much for your input!! PS- On the bright side, this MacBook is making the noise significantly less than the 2nd one.