My apologies, I don’t think I explained myself properly?
I tried various outputs from the Bluesound Node 2i to the Pontus.
1) My first try was the optical out of the Node 2i to the Pontus using a new optical cable and there was some very strong distortion after an hour of playback.
2) I tried another optical cable that I know is working and same problem.
3) I tried a very short coax cable, same problem.
4) I ordered a USB cable to use from my iMac using Roon and it starts off sounding excellent then after about 15 minutes I have a background white noise that overshadows the music.
UPDATE! Alvin Chee has sent me a firmware update that I will try and hopefully that will clear things up?
Bill