Help Intermittent Vibrate problem


has anyone had a satisfactory repair for the problem of intermittent vibrate on the Desire? Mine is not too bad, maybe lose vibrate once every week but it is massively annoying. It has been to HTC repair centre 3 times without success. The "tap it on the back of the phone" trick works well but obviously there is something wrong. My phone is only 6 months old but the problem has been there for teh past couple of months. HELP!!!!:eek: