Hmm ... hard to tell from the distance. Is the silent Icon placed outside the valid HotSpot area, maybe? (... but then it shouldn't play back anything at all.)

If the problem persists, please send the VI-Frame to our support - we will look into it.

 Kind regards,

@Philippe BAYLAC said:

Couldn't be a problem of latency ?

No, I don't think so - in case of a latency issue all instances would be affected.

As a matter a fact it was a problem of latency. I chose a larger latency value and the instance with the problem began to work. Thank you very much for the help.

Huh! Really?!? _One_ instance decided to stay silent while all others worked - due to a latency problem? Hmmmm ... *puzzled look*

Would you mind to tell us the detailed settings that lead to that occurence? TIA.

I studied the problem a bit more and I'll try to explain what happens. If in the VEP server the Vienna MIR latency is set to 0 it results in the following manner. Four of five instances are working and one plays back the dry signal. The problematic instance is always the one I have been feeding midi data last. For example if I have chosen the piano track and played some notes on my keyboard, the VEP instance containing the piano goes dry. If I then press play, all other four instances are working just fine. If I then play for example the trombone with my keyboard, the VEP containing the trombone goes dry and the one containing the piano starts to work again and so on. Does this make any sense.If you know the reason for this, that's good. If you don't I'm glad to offer any information you wish.

Interesting. Thanks for the info, Sami!

What system are you using for MIR Pro (OS, CPU, audio system)? And were you using MIR Pro stand-alone or in server mode?

Sorry, I'm not very good in these kinds of things, but I'll try to give you all the information you want. My system is:

Mac pro with 2xQuad-Core Intel Xeon 2,8GHz 16Gb RAM

Os X 10.6.8

Logic pro 8 with VEP5 in server mode

Apogee Duet as audio hardware

What more would you like to know?

Thanks, that should be sufficient for now. :-)

With Logic and VE Pro Server, MIR Pro latency of 0 is not very workable due to technical limitations unless you set the Logic's I/O buffer size to the same value as its Process Buffer Range (Small=512, Medium=1024, Large=2048).

I've noticed some weird stuff in terms of latency as well.  On the Windows 7 64 side if I set the RME FF800 latency to 1024 from 512 (VE Pro buffer X2) MIR's reverb return will start to cut out and sounds like a delay.  As soon as I put it back to 512 it is fine again.