Pontus 15th right channel output -crackle/slight distortion?

I've noticed an issue as per title. I've tried all manner of things to isolate the problem; ICs, tried different streamer/DAC, amp/pre amp, tubes in my pre amp but it's down to the Pontus. I've swapped left and right RCAs/channels on the Pontus outputs and the issue migrated to the left.

Very grateful if anyone has a possible solution or has experienced this themselves.

For context, the Pontus has been out of my system for a little while as I've been using a streamer/DAC, not sure if this would contribute

Thanks in advance 👍