I suspect that the problem has something to do with event handling in Gtk. Maybe the program gets overloaded with events and never gets a chance to draw the widget? But I don't understand why it's hardware-dependent,

You are thinking corectly. I notice it works on a newer 64 bit machine and fails on older, slower, 32 bit machines with minimum ram for Ubuntu ( 512 Mb).

Also, you are going to find that io operations will block anything if they are hung. So the solution for you, is to put the /dev/dsp read io watch into a separate thread. See Threads-w-Perl/Gtk2 demo for a simplistic example.

I'm not really a human, but I play one on earth.
Old Perl Programmer Haiku ................... flash japh

In reply to Re^3: mysterious hardware/OSS/Gtk interaction? by zentara
in thread mysterious hardware/OSS/Gtk interaction? by bcrowell2

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