How to change DVD-A groups on Linn Unidisk

A good friend has the Linn Unidisk 1.1. He had some problems with it, which have now largely been resolved by Linn. However, he has some DVD-A's which require the selection of "group two" in order to play back the high resolution (24/96) in two channel. He has a two channel system. How do you do this with the Unidisk, and does it require a video monitor? He and I would appreciate any advice from Unidisk owners.
I have a friend that works at sounds like music in the phoenix area and he is my linn connection.If he doesnot have the answer he can find it from linn in florida.

Kurk@Sounds like
good luck Dglinn
Glad to here that his problems have been taken care of. and
I think I can help with his problem has he attempted pushing surround on the remote and scrolling through the menu and choosing as he wishes. If that doesn't work may I also suggest two linn forums with plenty of people to help him with his questions. Hope this helps I have a video monitor hooked up to mine.
here are the forums
There was some talk on the uni disk on