Problem Groove Agent as VST in Cubase 8.5

Here after my problem.
I 've just bought Groove Agent 4 and want to set it as a VST instrument in Cubase 8.5 (64 bits).
When i want to route a midi track into Groove Agent 4, no sound is output.

  • it 's ok with Groove Agent SE into Cubase 8.5 (same configuration).
  • if I create a instrument track with Groove Agent 4, it’s also ok.

Is there a specific methodology for setting GA introduced with GA version 4 ? Is there an identified bug / limitation which shall required a fix ?

Thank’s for your support.