[timidity-talk] Strange glitch at start of default instrument (piano)'s output

[Martin G. <mar...@gm...>]

Hi and thanks for timidity, a truly wonderful program.

I'm writing because the Timidity bug tracker, like all the release
notes, seem to be down.

Here's the bug I am seeing:

Whenever I synthesize a MIDI piece using the default instrument, Grand
Piano, I get a series of random spikes in the first half second of the
right channel of the output - between 6 and 9 random samples at
seeming random moments, which sound like a harsh crackle. After these,
for the rest of the piece, everything plays perfectly.

This is on Ubuntu 16.04 (the current stable release, with Timidity
2.13.2) but has been happening since 2012 for sure.

Here is a minimal example of a single MIDI note, synthesized to a WAV

martin@score:~/audio/D-D/scores$ timidity -Ow -o note.wav note.mid
Playing note.mid
MIDI file: note.mid
Format: 1  Tracks: 2  Divisions: 480
Copyright: Copyright (c) xxxx Copyright Holder
Cue point: Created by Rosegarden
Cue point: http://www.rosegardenmusic.com/
Track name:
Playing time: ~4 seconds
Notes cut: 0
Notes lost totally: 0

The sound is the same when playing directly to the audio output.

I attach midi input and pictures of output, as well as a waveform view of the
whole noise phenomenon and a zoom of one-pixel-per-sample of the first
one. The wav file (400k) is at http://martinwguy.co.uk/test/note.wav

Am I the only one seeing/hearing this effect?

    M