Extremely irritating a/c scratching/cyclic noise

[ScratchyAC]

Hi everyone, I've had an utter nightmare since taking delivery of a brand new V40 T2 Momentum in the UK last July. I'm now on the second vehicle which has the identical intermittent issue (he original was replaced in September, after I escalated the matter and asked to be switched to another dealer who didn't ignore me via the HQ). It's really the most strange sound; when the a/c is on and engine running it will go from normal to a crunching, scratching sound like there are leaves in the system at any flow setting. When the engine auto-cuts out at lights the noise stops then re-starts with the engine. Happens both on auto-climate and manual adjustment. It's loud enough to be noticeable even with audio on so if anyone else has heard of this issue or found a solution please do let me know. It now essentially feels like I am being told by both the dealer (and the UK HQ) that I'm hearing things, they cannot replicate the fault (when it's with them) and won't allow me to reject the vehicle. I actually went for a test drive with an engineer in the car whilst the issue was happening, yet to my face the engineer claimed not to hear it. The finance company finally sent someone to check it out earlier this year but of course the issue wouldn't replicate on the engineers visit and so also are closing their complaint. I'm now being told by them to find an independent garage/mechanic, have them listen to it and put in writing they believe there to be a fault; Circles. Going around in.I thought Volvo was supposed to be a premium brand but I'm now unsure of that. Thanks