I wonder if anyone knows what the sound may be coming from my pc. Is a recent build and just now in summer in Spain I have noticed that the PSU makes a kind of strange noise when it has been running for a while
If it isn't too old, send it in to Corsair for a replacement.
From what reading I have done it is a somewhat common problem that happens to PSUs 5V standby rail. Didn't find any examples where it only happens after it has been running for a while. That could be a temperature related thing. Also seen the fan and the main capacitors blamed for this. Certainly doesn't sound like typical coil whine to me.