Audio input from computer is quiet at first

[korg4god]

I have connected my computer out to the line in on the PA5x. Every time I first play a song, mp3 or video the audio starts quietly and then builds slowly up to full volume. I've looked through every menu and page on the keyboard and can't figure it out. I use it for live performing where I integrate tracks and Karaoke videos to play with.

How do I fix this?

Thank you in advance,

Jeff

[korg4god]

It's like it fades in.