This is from Parky's link.
Originally Posted by Meridian - Hooking Up SpeakerLink
You can use any Ethernet cable as long as it is CAT5/6 and features STP (Shielded Twisted Pair)
Is it not possible to wire it using shielded cable just to compare?

Meridian are up to speed on magnetic isolation, that's the development of the ID41 from ID40., isolation.

I'm not saying the GISO doesn't work.