Ah good point about the lights - I might bring that up with him as a suggestion.
He responds well to my voice, and finds it soothing - I maintain a moderate tone when I talk. He has issues with my husband's voice, but that's because its naturally very loud (ie booming). Hubby has started to moderate it somewhat though, and is making a bit of an effort.
A lot of you have suggested Auslan, but he can speak - he's quite articulate and loves a chat. Will conversation not be possible? Oh wow you can see how confused I am.
Thanks for the info miss-delectable. I went to that Aussiekids site before I came here but there didn't appear to be any recent activity there, which is why I came here. We've only just started at a new school - and they are awesome. I'm hopeful for him that we won't have to move him yet again...