No audio after using wired headset...

[glitch]

I have had the same issue. The headphone jack on the 6700 is fairly cheaply made. There are contacts on 3 sides, one on the top, one on the right and 2 on the left. One of the contacts on the left is pushed into another when the headphone plug is inserted. This causes it to bypass the onboard speaker & mic. The left side contact is simply a thin plate sticking up from the solder point on the board which is then touched by another plate inside the jack that contacts the headphone plug. The distance between these two contacts is very, very small. If something conductive was to get inside there it would think there was always a headphone plugged in. This can be resolved using canned air or contact cleaner (very small amount, don't soak your phone).

What happened to me was that the left side contact actually seems to be bent just a little (this happened after getting a new headphone adapter that was a tighter fit than my original one). I've had my phone apart 3 times now to fix this issue and it still goes in and out sometimes. When it goes out and does not come back on it's own or with a gentle tap I've had success carefully sticking a toothpick in the jack and adjusting the rear most left side contact.

I've been looking for a place to buy a replacement headphone jack but have not had any luck yet. If anyone knows of a place to order one please let me know. I've found sites that will do the repair for me but the minimum I've seen is $75+ and I'd rather just do it myself since it'd be a simple repair if I can find the part.

On a side note, I have not upgraded or reflashed my phone yet, except for the official updates from verizion, so it's not related to WM6 or the current kitchens, at least in my case. If you search other forums it appears to be a fairly common issue.