Severe short term audio distortion when watching Netflix

Hi all , I can't find a reason for this anywhere - so posting as widely as possible

My Setup

New Win 10 PC with Matrix Element H USB card - Sablon 2020 cable to May KTE DAC - handmade Silver XLR's to Hegel H390 to Dynaudio Heritage Specials

For the last 12 nights, while watching Netflix or Youtube - the audio is swamped by severe high pitched distortion for 3-4 seconds , then all returns to normal

This only happens once per night - between 7 -10PM. Only once, never during the day and only for 3-4 seconds - all was good for more than the last 12 months with this current setup

I have contacted my internet provider - all is good from their end - have checked with a speed test as soon as distortion starts and speed is normal

I have replaced the Ethernet cable

I have uninstalled and reinstalled the Holo Audio driver for my MAY KTE DAC - on a suggestion from Microsoft Support

I have rebooted  PC several times and switched off May DAC and unplugged power cord for 30 seconds

Any ideas or suggestions appreciated



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Power co. - no joy - they just said everything looks fine from their end and couldn't give me any info on switching power feeds or transformers etc..

Have an ethernet cable from Internet wall box direct to PC , no modem, no wifi

The Netflix thing is a possibility , but the first night it happened, I was watching a movie on Youtube

Can you describe your Netflix issue more?

New spanner in the works - a few days ago, same 3 second burst happened twice in an hour while listening to wav. files stored on my PC... 🤣