Ditto on my X250.5 - definitely notice metal sorta clicking noise after powering down. I called Pass and they explained it was the thermal contraction in the heat sink causing the noise and that it was completely normal. This past weekend - i noticed clicking during warm up and got a bit worried. But glad to see I am not alone in noticing clicking during warm up. So far - it has not affected the SQ - its a solid performer otherwise!
