Every build of Csound 6 I've done on Linux, including one from Git 
tonight, has played back samples at what sounds like a radically 
reduced bit depth.  Grainy, distorted.  I get the same results using 
JACK, or straight ALSA (-odac).

I've never had this problem with my Csound 5.x builds.

Can someone else please test this CSD with Csound 6 on Linux?  Replace 
"track53-stereo.wav" with any stereo .wav or .aif file. 

If it's distorted the way it is on my system, it will be obvious.

--------------------------------------------------------------------------

<CsoundSynthesizer>
<CsOptions>
-+rtaudio=jack -B 1024 -odac:system:playback_ -d
;-odac -d
</CsOptions>
<CsInstruments>
sr      =  44100
kr      =  4410
nchnls  =  2
0dbfs   =  1

instr 1
asig1, asig2  loscil .5, p5, 1, p5, 0
              outs asig1, asig2
endin
</CsInstruments>
<CsScore>
; track53-stereo.wav: RIFF (little-endian) data, WAVE audio, Microsoft PCM, 16 bit, stereo 44100 Hz
f1  0     0  1   "./track53-stereo.wav"  0  0  0
i1  0     3  .9  1
</CsScore>
</CsoundSynthesizer>