HI,

thank you for the reply!
I have currently installed H9 Control v 2.1.1.

I removed manually the preferences but with no results…

But, finally this morning I resolved the situation!

I give you a fast report, maybe it should be useful to other H9 users with the same problem.

I checked the active processes list on my Mac and after some test I found that there is probably a conflict issue between H9 control and an old RME Fireface 400 driver (3.06).

I know, in my last post I didn't tell you anything about external audio interfaces, but till this morning I didn't know that it could be somehow relevant.

In synthesis, when the FF400 is not connected to the MAC the H9 Control startup process freezes on boot for about 5 minutes, I can't verify but I think that the RME driver lock something in Coreaudio on Mavericks 10.9.5.

Since I have some difficulties with the last RME FF driver (a bug on the encoder control, but this forum is not the place for such discussions), I found an intermediate version of the RME driver 3.19 and now everything is fine.

Hope this report could be useful for someone!

Thank you!