Error while using rewire - midi_mme: error 4 opening midi input device

Hi,

I'm having a problem while using Max as a rewire slave with Cubase SX3 as a host.

The problem comes and goes, which makes it quite frustrating. I'm getting the error message "error: midi_mme: error 4 opening midi input device USB Audio Device"

USB Audio Device being the name of my controller keyboard. I'm running the latest version of Max on a Windows XP machine. It has been working fine but sometimes when I load it up it gets this error and there doesn't seem to be any change in my set up at all.

I know there are other ways around this like sending the MIDI in to my sequencer then on to Max or using Pluggos but I'd really like to get to the bottom of this.

Has anyone ever seen this error message before and/or know a way to solve it.

Thanks in advance,

Peter Anderson