Update :-
I sent the Pro Plus back to the vendor (AV.com = Gear4music) as I was approaching the 30 day return window. In my experience these sort of problems are more likely to be systematic rather than random so decided to take the refund and purchase from another vendor on the basis that it would a different batch and less likely to have the same problem. So the new unit arrived yesterday from Amazon UK and guess what.....it has exactly the same problem. At least the remote works on this unit which was another ticket on the previous unit.
At this point, some of you are probably thinking I have my RCA cables mixed up. Indeed, that was the first thing I checked last time and I can assure you it is not the case. To eliminate any doubt (not that I really had any) I turned the voltages on the Wiim right down and connected the RCAs direct to my power amp - see photo below, dust and all! USB cable removed to take the photo. Played audio test file "This is the left channel" emanating from the right speaker. So I closed the old tickets and submitted a new one #499874 yesterday which has been escalated to the engineer team. I can also add that it works fine on a set of Bluetooth headphones.
With hindsight I should have picked up on this earlier and I was in my fourth week of ownership when I realised the problem. The background for those with time to read - not long after purchase I was comparing Joe Bonamassa's Blues Deluxe on Qobuz (remastered) vs a CD I purchased not long after release in 2003; synchronised the timing from the Wiim app and my CD player, then switch back and forth on the pre-amp. There is quite a broad percussion soundstage on this album and I noticed on Burning Hell the cymbals at the start were appearing on different channels. I put it down to the re-mastering, which I did think was a bit odd to move instruments from one channel to another. The upside was I thought the re-mastering sounded marginally better with a bit more space between the voice and instruments - perhaps the channel reversal suited my asymmetrical room better, or perhaps the re-mastering resulted in a better quality stream. Only when I decided to optimise my speaker placement with a few audiophile test tracks did I realise that the Wiim output channels were reversed. For that reason I would guess there is a multitude of units out there with reversed channels - they just haven't been noticed yet.
It has probably been stated on the forum already, but if you are raising a ticket for a technical problem, then do it from the Wiim app - bottom right "Settings" and then Feedback. I understand some diagnostic data will be sent to the team with your request, which won't happen if you submit from a web browser and you'll lose 24 hours.
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