I posed a question about this a while back, and Kai found the problem
and sent this workaround:
> ---------- Forwarded message ----------
> From: Kai Vehmanen <kvehmanen(a)eca.cx>
> Date: Thu, Mar 19, 2009 at 3:03 PM
> Subject: broken lame/mp3 output (was: Re: Problem with ecasound on CentOS 5.2, x86_64)
> To: MHR <mhullrich(a)gmail.com>
> Cc: ecasound-list(a)lists.sourceforge.net
>
> Hi,
>
> :
>
> Fortunately, a workaround is easy, just add:
>
> --cut--
> ext-cmd-mp3-output = lame -b %B -s %S -r --little-endian -S - %f
> --cut--
>
> ... to your ~/.ecasound/ecasoundrc and ta-daa it works.
>
This works nicely, so if anyone else was having this problem, here's the fix.
mhr