Getting Espeakup to open the soundcard instereo

[Geoff Shang]

Hi,

I'm trying to get Espeakup working with an external USB soundcard, due to 
the crash issues one faces when using Espeakup with the internal soundcard 
on the Raspberry Pi.

The problem I've run into is that the USB device doesn't know how to 
handle mono audio.  If I play a stereo file, it works fine.  If I play a 
mono one, it fails.

I suspect that Espeakup is failing for the same reason.

Since there doesn't appear to be any command line options to Espeakup to 
make it do this, I wondered if there might be some ALSA trickery, like 
using the ALSA_CARD variable to choose which soundcard to use.  All the 
solutions I've found so far however implement something at the plug level 
which would appear to be a bit high up.

Any thoughts on this?  This is fairly urgent.

Cheers,
Geoff.