Ive just resolved this same issue – here goes its a bit of a tale:
I had loads of creaking and discovered it was coming from my crankset. The RF Evolve XC cranks use a sinlge compression nut to pull them together. Anyway the splines have all worn on the NDS shaft. Sent to LBS who sent off to Orange – Orange offered me a crash replacment scheme of £90 for a new set as “RF were bust so we cant do anything about it”. I told them to send them onto Silverfish (but apparently Orange buy direct from RF in us/Canada – in the end they did send them..
So Orange finally sent them to Silverfish – who agreed there was play on the splines and they were knacked. However SF claims this was caused because they hadnt been tightened enough into the RF BB – I told him they were fitted to a Hope BB on an 2010 Orange Five with the Hope BB upgrade and he said they shouldnt have been. The RF BB needs to be used as it is designed to work with these cranks. Using them with the Hope BB means you put too much sideways load into the hope BB bearings. The RF allows for tightening of the cranks more and prevents the splines wearing – a perfect fit where the Hope one may be out a mm or so.
Anyway – Silverfish spoke with Orange about this and I dont know the outcome. What I do know is that my 12mth old crankset was knackered and I am being sent some new crank arms and a new BB – after about 7 weeks of me moaning at my LBS, Orange and Silverfish.
Silverfish were ok to deal with and have resolved the problem when they didnt need to they could have said its your own fault. Other than the issues about getting in touch with them they have been very good. I know they arent public facing so this is probably why.
So moral of the story – don’t upgrade your BB to Hope BB if your using a set of Race Face Cranks I suppose – or sell the RF’s and but Shimano HT2 type cranks.