[fluid-dev] Re: An evil screeching noise when playing

[Toby]

Kimmo Sundqvist wrote:
> it appears in 1.0.5 but not in 1.0.3.  Will try this out myself soon.

You should really try this out yourself, since you're apparently one of
the only people who experience this bug.  If this behaviour is
confirmed, you should also look at intermediate versions, like 1.0.4.
If you can use CVS you could narrow it down to a single CVS checkin.


> There is something in the midi file that [...] starts and stops the
> screech.

Identifying this 'something' would also be useful.  But only somebody
who experiences the bug can do it (ie. you.)


> Tried playing sabre_dance.mid.  It was ok for 10 seconds, then I
> noticed a clicking that got faster and faster, and suddenly the noise
...
> after the Sabre dance starts playing, Fluidsynth's CPU usage slowly
> (in about 10 seconds) climbs to 99% and stays there.

Wait a minute, does the screeching sound only appear after Fluidsynth
has been at 99% CPU for some time?  

 From what you say it seems like something is making Fluidsynth
gradually comsume more and more CPU until it reaches 99%, at which point
clicks appear (this is normal.)  But that something doesn't stop there
and makes Fluidsynth need more and more CPU, well beyond 100%.  Clicks
get faster and faster and after a while the CPU hogging reaches a point
where Fluidsynth cannot function properly anymore and the sound produced
becomes a senseless screech, a distorted shadow of its former self.

This is quite plausible behaviour and quite a different matter than
'something' in the MIDI file triggering evil screeches at random.

If this were the case, we'd be looking for a sort of 'CPU leak'
somewhere in Fluidsynth or maybe in your system's libraries or kernel.

Can you investigate further?


Toby