real-time render in place with external instruments


I’m having an issue with the real-time render in place function for external instruments. In general it’s working fine. E.g. If I create a new empty project, set up a new instrument track with an external instrument, record some midi notes and hit render in place it works just fine.

But I have just one particular project where it is just not working. I’m puzzled. It must be some settings within the specific project but I can’t figure it out. If I try to render my external instrument in real-time in that project, the window with the two progress bars opens, jumps immediately to 100%, creates a new audio track with no content and no audio was recorded at all. I know it’s not an easy question but maybe somebody else run into the some problem in the past.