Hello. I apologize for my poor English. I have a little annoying problem. In a song I play an intro live with a preset of Rapture Pro BEFORE pressing play song. After pressing play the song, and while I'm still playing the keyboard, the sound of the live synth is muted for an instant. Does anyone have a solution? Thanks so much

Try and increase your midi buffers, the default is very low, I set mine for over 1,000. 

Live MIDI input isn't affected by buffering. I'd have to check, but I'm guessing that starting the tranport resets the audio engine and/or interface ports in some cases. This may or may not be affected by preference settings like Always Stream Audio Through FX, Allow Arm Changes during Playback, and MinimizeDriverStateChanges in AUD.INI. And it may be more noticeable on some interfaces than others, depending on how quickly the driver responds to a port reset.

Thanks for the answer but in fact increase the buffer size has not responded the issue.

If your midi data starts at measure 01:01:000, try moving it out to 02:01:000

No. Midi data starts at measure 03:01:00

There is a language barrier here, but I think I can understand pretty clearly.
You press play and the synth is muted  for a second ?
 
what are you using for a soundcard ? and what are your buffers set at ?
 
This very well could be a case of latency.

Yes. I's exactly so. When I press play, the synth I'm playing is muted by less than a second. I have a Focusrite Scarlet 6i6 and the asio buffer size is set to 3 ms. I tried other values ​​but nothing happens.