Nord lead A1 velocity problem

Hello! I have just bought a used nord lead A1! Sounds very good but some of the keys (two groups of four keys) do not have any velocity at all. I was wondering if it is worth sending back the synth (i have buyer protection) or if repairing the little contacts is worth taking the risk. I will be probably playing hundreds of live shows with the synth and it has to be reliable so should i repair it or not? Thanks in advance, a slightly un-amused A1 owner (at the moment :slight_smile: )