A604n not working

Hi all,

I received my A604n with Indy ECS today. However, the A604n is not working.
When inserted the A600 just hangs. Nothing happens. The power LED comes on, the capslock LED comes on.
That is it. No video, no diskdrive activity. The Indie ECS is not mounted yet.

When I mount a different memory expansion the A600 works fine.

It seems something is wrong with my A604n.

I am using it on a rev 1.1 A600 with an ACA 600 on ROM 3.1

Is there some common issue you guys know of or have I just received a dodgy one?

Thanks.