[PD] Key-related audio glitch, OS X Intel

[Phil Stone]

More information on this:

> I've been playing with Miller's experimental version for Intel OS X (see 
> http://crca.ucsd.edu/~msp/Software/pd-imac-test.mac.tar.gz )
> and for the most part, it works great.
>   

[...]

> Typing on the computer keyboard (e.g. to enter something in a number 
> box) after focus has just transferred to PD, makes a crunch or pop in 
> the sound right at the moment of the first key press.  Subsequent key 
> presses do not interfere with the sound, until focus is switched to 
> another app (or maybe even another PD window -- I can't reproduce this 
> very consistently) and then is returned to PD. 
>   

More exacting testing shows that the glitch can be consistently 
reproduced using the simplest audio patch,  [osc~ 400] - [dac~]
or even the Media Menu -> Test audio app.

Window focus has nothing to do with it:  it is related to time.  If a 
key on the computer keyboard hasn't been pressed for n seconds (n equals 
about 10 on my system), the next key press causes a significant audio 
glitch.  Further key presses, if made within n seconds, don't cause a 
glitch.  *After any pause of n seconds or more, the next key press 
causes the glitch.*  Also, there need not be any key-input controls on 
the PD screen; as I said, the simplest audio patch can reproduce this.

> I've tried different latency settings and this has had no effect.
>   

The -rt startup flag makes no difference.  Completely disabling 
Dashboard, and effectively disabling Spotlight, makes no difference.

> This seems like some bad interaction between the OS key-handling and 
> PD. 
>
>   
I would really appreciate it if:
  a) someone on PPC OS X could see whether this happens to them.
  b) someone else running the experimental Intel version of PD (anyone?) 
could try to replicate this.

Also, I'd appreciate some noob-advice on whether I should I file a bug 
report on this.


Phil Stone
pkstone,   ucdavis