Is it just mine?

[Feng]

I have recently bought a Korg M3 desktop. While warming I can hear subtle crackles coming from the chassis (probably due to thermal expansion). Then it's silent and the same crackles appear when I switch it off (and the unit goes under another thermal gradient).
Apart from that the unit works like a charm.
Has anybody experienced this?

[Trinity2112]

I've heard mine "crackle" a few times when there's a significant temperature change.