ND5XS2 left speaker crackle

I noticed today out of the blue, no changes in setup or wiring a dusting crackle on my left speaker when playing from the ND5XS2. I put on a vinyl record and all was fine.

I first noticed crackle when playing from Roon today but it also came through when playing radio in the Naim/Focal app.

Here’s the strangest thing: it’s intermittent. Power cycling helps but then it comes back eventually

Any tips on troubleshooting?

Can you switch output to go via rca instead, and connect to the amp with standard interconnects?