This is an annoying little niggle. I have 3 pages of quick carts set up at the bottom of my screen.
The third page has instrumental backing tracks,
Whenever I select this page it causes a 2 second gap in whatever's playing. Which is very annoying and noticeable.
Only happens the first time I select the page. After that it seems OK.
When a page is accessed for the first time the audio for the players on that page are initialised. I can't reproduce the issue are you seeing/hearing, however. Where is the audio located, hard drive, external hard drive, SSD? What format is the audio - MP3/WAV? My thoughts are here are that if the audio is sufficiently large enough to load from disk it may detract from the audio that is currently being buffered in another player.
Do you experience the same issue when you are dragging and dropping tracks onto the carts?