[chuck-users] SndBuf causes hickup

Atte André Jensen atte.jensen at gmail.com
Tue Jun 12 16:18:08 EDT 2007


I have (and have had for as long as I can remember) problems with 
SndBuf. I'm pretty sure the trouble is when loading a sample, then there 
will most often be a small but very noticeable hickup. It's quite bad 
with larger samples but also there with even small samples. Generally; 
the larger the sample, the greater the hickup.

The problem seems to be gone or almost gone when the sample has already 
been loaded once, but this might be due to caching in the underlying os.

I've tested with both alsa and jack, and all kinds of combinations of 
buffersizes and what have you, but although the problem seems the vary a 
bit (in an unpredictable pattern) it's always there. I also tested both 
syntaxes ("sample" => s.read and s.read("sample")), however only with 
wav files. I also tried both in miniAudicle and commandline chuck.

Needless to say this makes SndBuf useless on my system :-(

Is this a result of me doing something wrong or a bug in chuck? In any 
case is there anything I can do to remedy this right now? If it's a bug, 
I'd be most happy to help in any way I can with getting it fixed as soon 
as the developers time permits.

BTW: This is under linux (debian/stable) on a IBM T41, 1.6Ghz, 1G ram 
and 7200 RPM HD. The system is running with a realtime patched kernel 
and is capable of playing back 20+ tracks in ardour with effects + 
various soft synths running along in realtime without a single xrun or 

Here's a simple example of something that shows the problem: 
http://atte.dk/download/sndbuf_test.tgz. First run shaker.ck, then after 
a while add substitution.ck (a beat => big hickup) or sd.ck (a snare 
drum => small  hickup).

peace, love & harmony

http://atte.dk       | http://myspace.com/attejensen
http://anagrammer.dk | http://atte.dk/compositions

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