Hello all, I have written a small oscillator application in C++ Fiddling with errors and producing output to see where I am brougt me to a question: I had only ``printf( "Processing ...\n" ); in my process callback. My program started to produce output the moment when ``jack_activate( client );'' is called. Isn't this a bit waste of CPU due to the fact that the process_audio callback copies plenty of data to a port which is not used yet? I'd expect to get output from this (nothing sounding yet) program at the moment when it calls ``jack_connect'' for now I have this in my oscillator constructor: ... code snippet ... make_wave(); jack_activate( client ); //FIXME: throw exception if an error with client activation //FIXME: this should be placed elsewhwere and replaced by: // jack_activate -> jack_connect for port connections // jack_deactivate for port disconnections // the process callback will be called for every activated client // even no port is connected consuming unnecesary CPU power } ... Is this intended behavior? I'll leave the workaround in the comments in my code snippet in place then. I am using JACK 1.9.10 on a Linux x86_64 machine # uname -a Linux frankies 3.13.0-79-lowlatency #123-Ubuntu SMP PREEMPT Cheers Frank