playback issue


I doing some piano work and when I try to playback, Dorico goes from 4% to more than a 100% use of the cpu.
I’m only using one staff routed via midi to a IAC bus. No virtual instrument in Dorico.

Anybody notice anything on the midi side of things with 3.5 ?

All the best


If you’re using an IAC bus, then have you checked that you’re not getting a feedback loop, so that every MIDI event is being echoed back to Dorico? Does this happen if you send to a different port?

Hello Paul

My Midi input is set to another device, but I changed the output IAC bus to see and I get the same result.


Can you run Help > Create Diagnostic Report and attach the file from your desktop here?

Here you go.
Thank you

Dorico (485 KB)

I can’t see any specific warnings in there, though I can see there’s a lot of IAC buses. Could you try creating a new project using the default HSO Playback Template and tell us whether the CPU usage goes up to 100%?

Paul, I just did a test with default HSO and I get the same issue.
here the file I’m working on. Flow 7 for example.

Yan (1.42 MB)

I wonder if you are experiencing the problem described in this thread?

Try pressing the F4 button to show the video window and then press again to hide it, and then try to play - is the CPU reduced?

Yes !
I’m now at 22%
I had never heard of this.

Thank you…