From: Paul Troughton <audacity@tr...> - 2003-11-28 17:57:15
Like Monty & Martin Hauptmann, I'm using the Emagic emi 6|2m (a.k.a.
A6|2m) 6 input USB soundcard. However, I'm trying to use it on yet another
platform: OS X (10.3.1).
Using the default PortAudio, Audacity 1.2.0-pre3 gives an "Error while
opening sound device" when trying to record more channels. PortAudio puts
"Invalid number of channels" in the syslog at the same time.
This appears to be caused by the PortAudio CoreAudio
interface, lib-src/portaudio/pa_mac_core/pa_mac_core.c, being unable to
change the number of channels associated with a device.
I tried using PortAudio v19 instead, but Audacity won't compile under
Panther with v19 selected (AUDACITY_1_2 fails while trying to build
unix_oss versions (which I don't believe it should be trying to do; the
HEAD CVS version runs into problems with ltconfig -- any suggestions
welcome). So, I don't know whether v19 would fix the problem.
However, on the PortAudio CVS server, there is a newer version of
PortAudio v18-patch (16 April 2003) than the one bundled with Audacity (3
Feb 2003), with several changes to the handling of multichannel sources
under OS X. Substituting this version of PortAudio into Audacity fixes the
problem, and may fix several others (such as mono iMic sources).
Is there a particular reason why Audacity is using the older version of
the v18-patch? If not, I'd recommend switching to the newer one. If so,
please tell me (so that I know what I'm letting myself in for if I try to
use this for serious recording work).