My hotmpoint dryer is jamming on start?

Hi, My Hotpoint VTD20 jams when I press the start button. This is when I have a normal load in there. It is ok - ish when there is a light load. By light load, I mean 3 or 4 t-shirts.
When it jams, I can smell a burning smell. I have in the past just moved the drum round and started it and it is kind of ok. Just tonight, the burning-out smell was quite bad so i decided just to leave an ultra-light load in there. I will not go to sleep until the cycle is done. Can anyone help me. I know it is dangerous to leave it unattended, so am reluctant to even use it. If it helps, I have an external duct.

Bob - no I'm not a builder
March 2009