Hi, I was getting what seem to be random crashes when testing some of live midi instruments. It seems that these crashes were being caused by me switching midi channels in an instrument with an empty `instr 128`. I tried to present a simpler instrument than the one, that I originally encountered the problem in. I also have shown the command output from a crashed session. For now I am just removing the dummy instrument from my own instruments, but it seems kinds of curious that this would cause a crash. thanks schwaahed crasher_simple.csd -d -m231 -H0 -s -W -+rtaudio=jack -odac:alsa_pcm:playback_ -b 128 -B 512 --expression-opt -+rtmidi=alsa -M hw:2,0 --midi-key=5 --midi-velocity-amp=4 ;-d -m231 -H0 -s -W -+rtaudio=jack -odac:alsa_pcm:playback_ -b 128 -B 512 --expression-opt -+rtmidi=virtual -M0 --midi-key=5 --midi-velocity=4 sr = 44100 ksmps = 10 nchnls = 2 gisine ftgen 0, 0, 65537, 10, 1 ; sine wave gi_tuningET ftgen 429, 0, 128, -2, 12, 2, 440.0, 69, 1.0, 1.05946, 1.12246, 1.18921, 1.25992, 1.33483, 1.41421, 1.49831, 1.58740, 1.68179, 1.78180, 1.88775, 2.0 massign 2, 22221 instr 128 ; dummy instr endin instr 22221 pset 0, 0, 0, 0 , 0 ; pset defaults for instruments all 0's in this case ;;; Amplitude Generation iamplitude = p4 ;;; Frequency Generation ifrequency cpstuni p5, 429 ;;; Music Envelope aenvelope mxadsr 0.004 , 0.5 , 0.25 , 0.05 asignal poscil iamplitude , ifrequency , gisine asignal = asignal * aenvelope ;;; damping/declick envelope iattack = 0.0015 irelease = 0.002 isustain = p3 p3 = iattack + isustain + irelease adamping linsegr 0.0 , iattack , 1.0 , isustain , 1.0 , irelease , 0.0 outs asignal*adamping, asignal*adamping endin i22221 0 3600 0 0 0 schwaahed@schwaabook ~/Programming/Csound/Patches/Good $ csound crasher_simple.csd Setting language of messages to English (US) ... time resolution is 0.462 ns virtual_keyboard real time MIDI plugin for Csound 0dBFS level = 32768.0 Csound version 5.03.1 beta (float samples) Nov 9 2006 libsndfile-1.0.17 UnifiedCSD: crasher_simple.csd STARTING FILE Creating options Creating orchestra Creating score orchname: /tmp/fileKJWfH7.orc scorename: /tmp/fileRf5dFg.sco rtaudio: JACK module enabled rtmidi: ALSA module enabled orch compiler: 51 lines read instr 128 instr 22221 Elapsed time at end of orchestra compile: real: 0.002s, CPU: 0.000s sorting score ... ... done Elapsed time at end of score sort: real: 0.002s, CPU: 0.000s Csound version 5.03.1 beta (float samples) Nov 9 2006 midi channel 1 using instr 128 midi channel 2 using instr 128 midi channel 3 using instr 128 midi channel 4 using instr 128 midi channel 5 using instr 128 midi channel 6 using instr 128 midi channel 7 using instr 128 midi channel 8 using instr 128 midi channel 9 using instr 128 midi channel 10 using instr 128 midi channel 11 using instr 128 midi channel 12 using instr 128 midi channel 13 using instr 128 midi channel 14 using instr 128 midi channel 15 using instr 128 midi channel 16 using instr 128 displays suppressed PSET: isno=22221, pmax=5 ..0.000000....0.000000....0.000000....0.000000....0.000000.. 0dBFS level = 32768.0 ftable 101: ftable 429: chnl 2 using instr 22221 ALSA: opened MIDI input device 'hw:2,0' orch now loaded audio buffered in 128 sample-frame blocks writing 512-byte blks of shorts to dac:alsa_pcm:playback_ SECTION 1: new alloc for instr 22221: nxtopds = 0x813a264 opdslim = 0x813b204 WARNING: rtjack: xrun in real time audio rtevent: T 2.708 TT 2.708 M: 0 0 new alloc for instr 128: midiKey: pfield: 5 value: 66 midiVelocityAmp: pfield: 4 value: 13901 rtevent: T 2.804 TT 2.804 M: 0 0 ctrl 120 has no exclus list ctrl 120 has no exclus list rtevent: T 6.725 TT 6.725 M: 0 0 midiKey: pfield: 5 value: 49 midiVelocityAmp: pfield: 4 value: 13901 rtevent: T 6.920 TT 6.920 M: 0 0 rtevent: T 8.191 TT 8.191 M: 0 0 midiKey: pfield: 5 value: 50 midiVelocityAmp: pfield: 4 value: 13901 rtevent: T 8.252 TT 8.252 M: 0 0 new alloc for instr 128: *** glibc detected *** csound: malloc(): memory corruption: 0x08135710 *** ======= Backtrace: ========= /lib/libc.so.6[0xb7d77dff] /lib/libc.so.6[0xb7d78f16] /lib/libc.so.6(calloc+0xd4)[0xb7d79fb4] csound[0x805fdf6] csound[0x805ccd9] csound[0x805e084] csound[0x806271b] csound[0x80628e1] csound[0x806302f] csound[0x804b7db] csound[0x804b1dc] /lib/libc.so.6(__libc_start_main+0xe2)[0xb7d29852] csound[0x804a7c1] ======= Memory map: ======== 08048000-080d0000 r-xp 00000000 08:05 595219 /usr/local/bin/csound 080d0000-080d7000 rw-p 00087000 08:05 595219 /usr/local/bin/csound 080d7000-0814c000 rw-p 080d7000 00:00 0 [heap] b7600000-b7601000 ---p b7600000 00:00 0 b7601000-b76c2000 rw-p b7601000 00:00 0 b76c2000-b77dc000 r-xp 00000000 08:05 597968 /usr/lib/libxml2.so.2.6.26 b77dc000-b77e1000 rw-p 00119000 08:05 597968 /usr/lib/libxml2.so.2.6.26 b77e1000-b77e2000 rw-p b77e1000 00:00 0 b77e2000-b77e6000 r-xp 00000000 08:05 2578312 /usr/lib/libXdmcp.so.6.0.0 b77e6000-b77e7000 rw-p 00003000 08:05 2578312 /usr/lib/libXdmcp.so.6.0.0 b77e7000-b77e9000 r-xp 00000000 08:05 1692281 /usr/lib/libXau.so.6.0.0 b77e9000-b77ea000 rw-p 00001000 08:05 1692281 /usr/lib/libXau.so.6.0.0 b77ea000-b77f2000 r-xp 00000000 08:05 3513567 /usr/lib/libXrender.so.1.3.0 b77f2000-b77f3000 rw-p 00007000 08:05 3513567 /usr/lib/libXrender.so.1.3.0 b77f3000-b7861000 r-xp 00000000 08:05 537890 /usr/lib/libfreetype.so.6.3.8 b7861000-b7864000 rw-p 0006e000 08:05 537890 /usr/lib/libfreetype.so.6.3.8 b7864000-b7887000 r-xp 00000000 08:05 2659037 /usr/lib/libfontconfig.so.1.1.0 b7887000-b788f000 rw-p 00022000 08:05 2659037 /usr/lib/libfontconfig.so.1.1.0 b788f000-b7955000 r-xp 00000000 08:05 1108865 /usr/lib/gcc/i686-pc-linux-gnu/3.4.6/libstdc++.so.6.0.3 b7955000-b795a000 rw-p 000c6000 08:05 1108865 /usr/lib/gcc/i686-pc-linux-gnu/3.4.6/libstdc++.so.6.0.3 b795a000-b795f000 rw-p b795a000 00:00 0 b795f000-b7a51000 r-xp 00000000 08:05 3927595 /usr/lib/libX11.so.6.2.0 b7a51000-b7a56000 rw-p 000f1000 08:05 3927595 /usr/lib/libX11.so.6.2.0 b7a56000-b7a64000 r-xp 00000000 08:05 1147208 /usr/lib/libXext.so.6.4.0 b7a64000-b7a65000 rw-p 0000d000 08:05 1147208 /usr/lib/libXext.so.6.4.0 b7a65000-b7a76000 r-xp 00000000 08:05 522200 /usr/lib/libXft.so.2.1.2 b7a76000-b7a77000 rw-p 00010000 08:05 522200 /usr/lib/libXft.so.2.1.2 b7a77000-b7ae6000 r-xp 00000000 08:05 3962831 /usr/lib/fltk-1.1/libfltk.so.1.1 b7ae6000-b7aec000 rw-p 0006e000 08:05 3962831 /usr/lib/fltk-1.1/libfltk.so.1.1 b7aec000-b7aef000 rw-p b7aec000 00:00 0 b7aef000-b7b0d000 r-xp 00000000 08:05 275259 /usr/lib/libjpeg.so.62.0.0 b7b0d000-b7b0e000 rw-p 0001d000 08:05 275259 /usr/lib/libjpeg.so.62.0.0 b7b0e000-b7b1f000 r-xp 00000000 08:05 2827442 /lib/libz.so.1.2.3 b7b1f000-b7b20000 rw-p 00010000 08:05 2827442 /lib/libz.so.1.2.3 b7b20000-b7b44000 r-xp 00000000 08:05 848001 /usr/lib/libpng12.so.0.12.0 b7b44000-b7b45000 rw-p 00024000 08:05 848001 /usr/lib/libpng12.so.0.12.0 b7b54000-b7b74000 rw-p b7b54000 00:00 0 b7b74000-b7b80000 r-xp 00000000 08:05 3962833 /usr/lib/fltk-1.1/libfltk_images.so.1.1 b7b80000-b7b81000 rw-p 0000c000 08:05 3962833 /usr/lib/fltk-1.1/libfltk_images.so.1.1 b7b81000-b7c3f000 r-xp 00000000 08:05 3909229 /usr/lib/libasound.so.2.0.0 b7c3f000-b7c44000 rw-p 000bd000 08:05 3909229 /usr/lib/libasound.so.2.0.0 b7c44000-b7c4c000 r-xp 00000000 08:05 1108549 /usr/lib/gcc/i686-pc-linux-gnu/3.4.6/libgcc_s.so.1 b7c4c000-b7c4d000 rw-p 00007000 08:05 1108549 /usr/lib/gcc/i686-pc-linux-gnu/3.4.6/libgcc_s.so.1 b7c4d000-b7c55000 r-xp 00000000 08:05 595368 /usr/local/lib/csound/plugins/libvirtual.so b7c55000-b7c56000 rw-p 00007000 08:05 595368 /usr/local/lib/csound/plugins/libvirtual.so b7c56000-b7c64000 r-xp 00000000 08:05 3765212 /usr/lib/libjack.so.0.0.23 b7c64000-b7c66000 rw-p 0000e000 08:05 3765212 /usr/lib/libjack.so.0.0.23 b7c66000-b7c6e000 rw-p b7c66000 00:00 0 b7c6e000-b7c72000 r-xp 00000000 08:05 595361 /usr/local/lib/csound/plugins/librtjack.so b7c72000-b7c73000 rw-p 00003000 08:05 595361 /usr/local/lib/csound/plugins/librtjack.so b7c73000-b7cb9000 r-xp 00000000 08:05 595351 /usr/local/lib/csound/plugins/libstdopcod.so b7cb9000-b7cbd000 rw-p 00046000 08:05 595351 /usr/local/lib/csound/plugins/libstdopcod.so b7cbd000-b7cdf000 r-xp 00000000 08:05 595338 /usr/local/lib/csound/plugins/libstdutil.so b7cdf000-b7ce0000 rw-p 00022000 Csound tidy up: Aborted