Phone ringer turning itself off when set to vibrate...

[Druu]

Hi, I did a search and couldn't find an answer, and I also mentioned it in the 5067 thread, but didn't get a solution there either. Basically when I have my phone set to vibrate, after a while I'll check it and it will have set the ringer to off. Someone else who had a similar problem said he traced it to being a bluetooth problem, mainly with plantronics brands. Unfortunately I just bought a jawbone and it still does it. Has this been brought up before and is there a solution? Thanks!