Very strange...
I ran csound with -odac:0 and received the following:

matt@waterStone:~/csound/ch1$ csound -odac:0 101.orc 101.sco
Localisation of messages is disabled, using default language.
time resolution is 1.000 ns
PortAudio real-time audio module for Csound
PortMIDI real time MIDI plugin for Csound
0dBFS level = 32768.0
Csound version 5.07 beta (float samples) Nov 22 2007
libsndfile-1.0.17
orchname:  101.orc
scorename: 101.sco
rtmidi: PortMIDI module enabled
rtaudio: PortAudio module enabled ... using blocking interface
orch compiler:
11 lines read
        instr   101
Elapsed time at end of orchestra compile: real: 0.068s, CPU: 0.000s
sorting score ...
        ... done
Elapsed time at end of score sort: real: 0.085s, CPU: 0.000s
Csound version 5.07 beta (float samples) Nov 22 2007
graphics not supported on this terminal, ascii substituted
0dBFS level = 32768.0
orch now loaded
audio buffered in 256 sample-frame blocks
PortAudio V19-devel
PortAudio: using ALSA device '0'
Expression 'ret' failed in 'src/hostapi/alsa/pa_linux_alsa.c', line: 996
Expression 'AlsaOpen( &alsaApi->baseHostApiRep, params, streamDir, 
&self->pcm )' failed in 'src/hostapi/alsa/pa_linux_alsa.c', line: 1153
Expression 'PaAlsaStreamComponent_Initialize( &self->playback, alsaApi, 
outParams, StreamDirection_Out, NULL != callback )' failed 
in 'src/hostapi/alsa/pa_linux_alsa.c', line: 1362
Expression 'PaAlsaStream_Initialize( stream, alsaHostApi, inputParameters, 
outputParameters, sampleRate, framesPerBuffer, callback, streamFlags, 
userData )' failed in 'src/hostapi/alsa/pa_linux_alsa.c', line: 1925
 *** PortAudio: error: -9993: Illegal combination of I/O devices
Failed to initialise real time audio output
inactive allocs returned to freespace
end of score.              overall amps:      0.0
           overall samples out of range:        0
1 errors in performance
Elapsed time at end of performance: real: 0.398s, CPU: 0.020s
Removing temporary file /tmp/filebmDe4q.srt ...

And then afterwards ran it only with -odac and it worked fine.
I had this same kind of random working and not working before, then it went to 
completely not working.
I don't know.. for now its working.. we'll see where it goes...

Matt