got mine at Wal-Mart as well. 14 days return are long over. I have a slight rattling sound on vibrate. Not too concerned but wanted to see what Nokia had to say. Here is what I received as an answer (below). If I can convince somebody at an ATT store that the phone is different then I should be able to exchange it.
Originally Posted by shergillwp8
Thank you for emailing Nokia Care.
We understand the issue that you are encountering with your Nokia Lumia 920. We would like to advise that you coordinate with your network service provider (AT&T) to test and verify if this matter is also occurring to other Nokia Lumia 920 devices. If you have determined that your phone has a different condition comparing with other devices, we suggest that you request a replacement for your Nokia Lumia 920 as the issue occurring in your phone is a valid reason for replacement.
We hope for your kind understanding and we would appreciate your cooperation regarding this matter.
If you have any additional questions, please do not hesitate to contact us again. To ensure proper handling of your case, please continue using the current subject line.
You may also call Nokia Careline at 1-888-665-4228 from Mondays to Fridays at 9:00 a.m. - 9:00 p.m. EST and on Saturdays from 10:00 a.m. - 7:00 p.m. EST for immediate assistance.