Distortion/ noise using coaxial output

[Blackpesth]

I have a new WiiM pro since last week and it was working fine for 2 days then every time I play a song from wifi to coaxial output I can clearly hear noise / hiss and distortion.
I did try to switch back to my node 2i via exact same coaxial cable and power line and no noise at all
Both using same song , same wifi setup .
I did try to reset to factory default my WiiM but it didn’t solve the problem .
Is there something I can do before sending it back for a refund ?? Thanks

 

[goodmore]

People that have tried third party coax cables have reported that some do not seat the connection. Just a thought.

 

[ratty]

I have a new WiiM pro since last week and it was working fine for 2 days then every time I play a song from wifi to coaxial output I can clearly hear noise / hiss and distortion.

What's at the other end of the cable? Is that DAC capable of displaying whether it's losing clock sync? Is anything explicitly grounded?