I noticed on your website you said the bash shell was slow while the player is running.

This is probably as the player is running at 'real time' priority and bash isn't.
If you modify your shell call to set the priority of the nc command line to real time too before you run it, you should find that the shell is just as responsive as it normally would be.

With the player 'not playing' it should not cause any undue load on the system this way. You may even find it acceptable to use bash while the player is running/playing a song.

I'm not sure what system call you need to change the priority. I guess someone with the source code could tell you [but then they'd have to shoot you...].

I'm no linux hacker on this but getpri()/setpri() is a pair of system calls I remember from way back.
May also be a ioctl or 2?