hmm, tough luck then.
quite a mystery!
keep us posted if it gets solved; i just installed an srf3 myself and no problems yet but as they say, knowledge is power

p.s. i did just think of something else; have you been shifting while pedaling, or allowing the bike to coast while the hub switches gears? i just learned from the shop that made my wheel that the best thing is to shift Without pedaling... dunno about the mid-to-long term effects of doing it 'the wrong way' (aside from a pretty awful noise, and feeling some awkward pedal drag).