worth a go
Hollowtech II's BBs are always sh1t, try a company called superstar components, they retail at £20 a pop, and use slightly larger bearings than the Shimano ones, hence last longer, as for the jet wash......baaaaad idea...bye bye bearings!! to stop rust... dont ride int the wet
or give the axle a good grease before putting them in, and then after every ride take the seat tube out and let the inside of the frame dry out, ideally at house temperature!