buzzing dimmer on 3 way circuit with intermediate

I have 5 low volatge ceiling spots each with its own electronic transformer. There are 3 switches controlling the circuit, one of which is an intermediate. I've been trying to add a dimmer to one of the non intermiedate positions but every dimmer I try gives off a load buzz - too noisy to live with. I've tried quite a few dimmers but no joy. Is the circuit suitable for a dimmer? If so which poistion should it go in? or is there a special tpye of dimmer needed?

It can go in either of the 2-way switch positions, but of course if you use one of the other switches you'll get the brightness to which the dimmer happens to be set.

And yes - you need a compatible dimmer and transformers.

The transformers need to be suitable for dimming, and the dimmer switch needs to be suitable for dimming transformers. However, even if on the face of it you may have a dimmable transformer and a dimmer switch which will do transformers, you aren't necessarily out of the woods. You also need to match the type of dimming that it does to the type the transformers need, for example MK dimmers do it on the leading edge, and so can't be used for transformers which require trailing edge dimming.

See http://uk.altavista.com/web/results?tlb=1&fr=tb&kgs=0&ienc=utf8&q=+leading++trailing++edge++dimmer* for more info.