Thanks Jordan for taking the time to write that. However I get [chuck]: HidIn: couldn't open keyboard 1... and no change with d or h Looking at your code I gathered I should try 0 or 1. Same result Tried it in console (not X windows) Still same. Fished around in google and came to this on the wiki http://wiki.cs.princeton.edu/index.php/ChucK/keyboard So by some guesswork I changed your function keyboardListener to this: [This is the first chuck I am writing!] fun void keyboardListener() { KBHit hi; int c; while(true) { hi => now; while(hi.more()) { //if(msg.isButtonDown()) hi.getchar() => c; { if(c == 68) // d 2 *=> Voice.multiplier; else if(c == 72) // h 2 /=> Voice.multiplier; else if(c == 73) // i Voice.decreaseSpread(); else if(c == 79) // o Voice.increaseSpread(); } } } } At first it did not work until I realized that the d h should be upper case. Now I get my basic effect. I cant hear any effect from i/I or o/O but thats minor. Trying to reduce the jumps to less than half/double I changed the 2 to 1.5 It just goes silent Changed the 2 *>= Voice.multiplier; to 5 +=> Voice.multiplier; chuck dies and I get cpu 100%.