If they see the noisy PSU as a fault then it'll be a free swapout, but they will only swap if there is an issue. My SH1 was swapped out due to an intermittent network fault that kept bumping up the latency (think broadband graphs were showing no black just green/blue/yellow and red)
Weird thing is though that they've just sent me a new SH2AC to replace the SH2 with my new TV box
That reminds me need to update TBB graph with new IP