Conclusion: The first one had an audible noise when using the USB, so I sent it back, received a new one and after a week the GPS just stopped working. So again, I sent that one back. So now, I am on my third unit, and so far it’s been working for two weeks as of May 24, 2012, but time will tell (Sonic has been great. I contacted the MFG and I cannot say the same). All three units also responded a little differently. This unit, the GPS has a lag in it.