how about you switch your PS3 UPS with the X360 one to see if it really is faulty?
even better, since you don't use both at the same time... just use one UPS for the 2 consoles... it requiers bending over and switching plugs but it's much cheaper...
(though if you're in a contry where power cuts all the time and you also have money for PS3 X360 computers, tvs, inverts, 300 UPS.... I guess the price of the unit is irrelevant to your comfort...)
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