Sleeping has never come naturally to Murphy

I am sure if he could he would stay awake 24 hours.
He sleeps in a crate in our bedroom and when we first got him he would sleep straight through to 8am. Unfortunately, this hasn't lasted.
He has started waking us up earlier and earlier to the point where this morning it was 5.30am

I am pretty sure there aren't any health issues. The first thing he wants to do is play with his new found love, his tennis balls. Toileting isn't the issue. Sometimes he won't ask to go out for ages after getting up.
We have tried taking him out for a long walk before bed. Feeding more/less earlier and later. Nothing makes any difference. Last night I even switched the central heating off in case the sound of it was waking him up.
Because I work shifts my wife prefers him in the bedroom with her but things can't go on like this. I am starting to feel ill as my shift pattern means I can't really have an early night to make up for getting up soo early.
I am thinking of letting him sleep in the kitchen but as he has slept in our bedroom for four months I can't see this being well received.
How can we get more sleep
