Sky Puck - pixelating

[Virus+issue]

We've had Sky glass for over a year now and had no trouble with the puck - until now.

Frequent pixilating regardless of content origin.

We've:

1. Re-booted.
2. Changed from wired LAN to wireless - no difference.
3. Rebooted main house router and discs - no difference.
4. Incoming internet is fine and normal (78mbs).
5. Main Glass unit is 100% fine on both wireless and LAN.

Any suggestions please?

Thanks

Sarah