Same problem here too.
I have been in contact with both HTC and Verizon and this is a know issue.
For anyone considering returning their TB during the evaluation window, so you don’t get stuck with bad video / sound recording on your phone, waiting to see if a fix is coming or not. You may want to consider checking with your Verizon store manager to see if they will extend the evaluation period.
I was able to negotiate with my local Verizon corporate store manager a 60 days window vs the standard 14 days to return my TB, if no fix is available by then for this issue.
Overall my wife and I like our Thunderbolts. We purchased two on the release date, and I first reported this problem to the Verizon store I purchased them from on 3/23 (where I also proceeded to piss off two Verizon employees that just got their TBs and they found out they had the same problem with their phones as well).
I also reported this issue directly with HTC early last week and was emailed a possible fix, which did not work. This later included several email exchanges on this issue, including me sharing with HTC on some results from basic tests I had preformed. In the end HTC escalated this to their development team.
This past Saturday (3/26) I returned to the Verizon store prepared to return both our TBs. I also provided Verizon a copy of the email exchange I had with HTC on this issue. They checked Verizon’s tech support system and this problem was showing as a known issue with no resolution listed at this time.
A Verizon tech support person did perform a Factor Data Reset on my TB, something HTC suggested but I had not done. However, after doing so there was no improvement. Since I never downloaded any additional Apps that may have changed any factory settings, I felt doing a factory data reset was not really needed, but allowed them to do.
After all this the manager tried to explain that a fix was most likely coming for this issue, but could not say when. I informed him I was unwilling to wait and risk if a fix was coming or not, or when, and considering the price of the phone I wanted to return them and reactivate my old phones. I then suggested that since I generally liked the Thunderbolt I would be willing to give HTC / Verizon a little extra time to provide a fix if he would be willing to extend my evaluation time to return my phones, without penalty, if a fix was not provided in a timely fashion.
After some discussion he offered me a 60 day grace period to return my phones if no fix was available by then. He logged this information into my account and provided me a printout for my records showing I have 60 days to return TB for this issue.
The one thing I had going for me is that these were my first upgrade to a smart-phone. As such if I did convert back to my old phones which were just under a voice plan on, Verizon would have been out two data and text packages which would have been dropped from my account.