just to add my 2 cents worth, i would say nearly ALL of the IP500v1's i know of, have had the power supplies die now. i think we have a handful of clients with V1's still working.
Tisco's do repairs on the power supplies here in NZ, but you need to drive the chassis down the road, possibly still smoking? and they get the soldering iron out.
from an electrical point of view, the other units still working, are REALLY noisy! pre death, the units have all just randomly rebooted. something breaking down... fire hazard Avaya??? no admission of crap power supplies.. guess a certain supplier got reamed before the IP500v2 went to market with mucho testing!
There most definitely is something wrong with the V1 power supplies. something is weak there... just do em a deal on v2 and move on happily.