KEF LSX: Crackles

I have my LSX connected via ethernet and both speakers are connected as well.
After 2 days of not using the speakers, when I start listening to music again the sound crackles.
I’ve returned them once to KEF and upon return it exhibited the same behavior.
So we did an RMA and they came and they continue to crackle.
It occurs whether I use KEF streaming or Airplay.
I have moved the speakers around my home office and into the master bedroom
And the problem continues. I’m on the latest firmware, 5.2
Am waiting to hear back from KEF support again