My Lumia 620 vibrates onli once in ring+vibrate mode..it doesn't vibrate for d entire duration of ringtone..is dis a bug or a hardware issue vit my fone?no issues in vibrate-only mode.
It sounds like a hardware issue, because I can't find any information about it, so I don't think it's a common problem. You could try a hard reset, but that will remove all your data.