Hi, David!
Not a bad question at all. If this isn't yet there I think this example should state in a comment that you need to enable multiple channels when starting ChucK.
From memory the syntax for 6 channels is;
chuck --chan6 --loop
You can do a lot more with those, see
chuck --help
For the exact syntax.
ChucK --probe
will tell you how many channels max you have at your disposal for various interfaces.
Yours,
Kas.