I admit I didn't take time to run the given orc/sco myself, but from
looking at the Csound output, I think I can guess what's wrong.  There
are only two notes in the score, and look at the amplitude each one
reaches, as given in the output:

new alloc for instr 1:
B  0.000 ..  4.000 T  4.000 TT  4.000 M:19043136.019462674.0
new alloc for instr 2:
B  4.000 ..  9.000 T  9.000 TT  9.000 M:  10000.5  19708.7
end of score.          overall amps:19043136.019462674.0

The amplitude of the first note is ~1900x the second one.  My guess is
that after the output floats are rescaled to 16-bit ints (I'm assuming
you're using that handy feature of the Mac version), the second note is
being pushed down into the noise (~65dB below the 1st note).  When you
comment out the first note, then the rescaling brings the 2nd note up to
16-bit full scale, so you can easily hear it.  So, if you want to hear
them both, you need to do something to reduce the difference in the amplitudes.

i changed it to ...

instr 1

	kenv1 linseg p4/3,p3/4,p4,p3/4,p4/2,p3/4,p4/2,p3/4,0
	
	asig1 oscil kenv1, cpspch(p5), 1
	asig2 oscil kenv1, cpspch(p5/2), 1
	asig3 oscil kenv1*0.2, cpspch(p5*2), 1
	
	outs asig1*asig3/p4, asig2*asig3/p4

;            ^^^^^^^^^^^^^^  ^^^^^^^^^^^^^^

endin


and it all works exactly as expected.  thanks all for pointing it out.  il
try to come up with a better mistake next time (:

-j
------------------------------
                    jti@io.com
                    http://www.io.com/~jti/
                    http://www.sonictherapy.com/fluoroscopic/fk.html
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