My brother-in-law's went completely dead, but I found a guy on one of the digital broadcasting sites, who fixed it very reasonably - if you want I'll see if my BIL still has the details.

Psion certainly have nothing to be proud of with this product, a good regulated 12volt supply certainly helps, as does a powered USB hub (particularly, I understand with XP) and removing the LED's also helps, if you haven't actually done it, a good description is here.
However, I found that none of these things helped as much as a good external dab aerial.
It still isn't 100% though, I only use it for timed recordings, which I edit with direct cut and download to the Empeg. You still come back to find a 0db file from time to time, so I've taken to doing a paranoid back up recording of the FM broadcast, on tape and if all fails, I retrieve it from radio player.

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