Hi guys,
I got my replacement for r6pro after the RMA procedure from Hiby. First look - I got the device, produced in May 2019. The box is from the player made in January.
First listening showed that RF EMI almost disappeared. Hiss and clicks are less pronounced, but still hearable. Also with 55 Ohm IEMs with 108db sensivity. I feel some disappointment.
I read replies here in the thread that the hiss caused by the powerfull amp part. But comon, I had fiio e12diy amp with Muses opamps installed and there was no hiss in the background. The same headphone, but completely black blackground and no clicks of switching of the amp part. Hiss & click takes place @ both 4,4 and 3,5 SE ports. I presume it's the component issue, which is used in both circuits.
Frankly speaking I would give Fiio M11 a try if it has somehow UAPP working. Cayin n6ii is 30% more expensive. It would be good to find a solution.