Jim-he's tried that already, and has also flashed a new ROM which has the same effect
This is definitely a hardware fault somewhere in the charging circuit as the battery charges in another Orbit, and the USB socket is OK. The only other thing to try is to borrow your mate's charger, to see if that works. It's a slight possibility that your charger has ceveloped a fault and is delivering a lower charge than required (HTC devices need a good 1A supply); once the device battery gets below a certain level, USB charging also ceases to work.
I suppose to test that you need to get your battery 50% charged in your mate's Orbit, then see if USB charging works from your PC (if you haven't done already!)
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