Post window says:
-> Synth('temp__0' : 1000)
RESULT= 0

With 3.8dev (linux) I only get an error, no crash:

ERROR: a PlayBuf: wrong number of channels (nil)

PROTECTED CALL STACK:
    MultiOutUGen:initOutputs    0x332de80
        arg this = a PlayBuf
        arg numChannels = nil
        arg rate = audio
...

Full error here

@patrickdupuis do you have any extensions that might be overriding core Buffer methods?

As far as I can see in the main 3.7 class library, the crash should be impossible -- as gusano noted, Buffer:play should fail even to build the SynthDef. The only ways that Buffer:play could be sending a SynthDef and trying to play anything in this case are:

• the play method is overridden somewhere with a buggy, unsafe alternative;
• or, something else is overridden so that the Buffer object's default numChannels is a number (rather than nil, as in the main library).

Disregard my last comment. It's a genuine bug in 3.7 that is fixed in 3.8.

We should backport the fix into 3.7. Commit = 727f7b3

No need to backport IMO, 3.8 will come out in 12 days.

This can be closed, no?