AKAI EWI USB does not work anymore in C7

Hi everybody,

I am using an AKAI EWI USB and different VST Instruments from samplemodeling. It used to work perfectly and I did not even have to think about it. I just plugged the EWI into an USB port, configured the ARIA software, started Cubase and I was ready to go.
Since one week or so I do not get any signal from the EWI into Cubase 7 nor Cubase 6. No signal from the ARIA VST, no signal from samplemodeling SWAM, no signal from samplemodeling instruments in Kontakt.
The ARIA standalone player works. The midi input list in Cubase shows the EWI. Probably I am missing something totally stupid, but I cannot figure it out. Can somebody help me?

Thanks in advance
Jochen