Indeed ! I didn't know this at all.

Aware of this I've just tested with greater values.
The problem disapears with value 224 (and is still there for 223, 222,
etc.).

(And I don't know what a value of data1=223 means...)

http://www.gweep.net/~prefect/eng/reference/protocol/midispec.html

There you go.
That should help. Before you spend as much time jugeling HEX and "normal" decimal values as I did; it turns out ChucK can deal with HEX numbers too.

Oh, and maybe this would also be interesting;
http://www.rattus.net/~packrat/audio/ChucK/

...but I still think this Win-Linux difference has you stuck at the moment.

Kas.