from the backtrace it seems like dosbox is trying to shutdown. But maybe the stack is already to corrupt to exit (frame #6 is E_Exit).

So doom2 with plutonia.wad doesn't work correctly in dosbox. (at least with the auto/dynamic core)

One more thing here - on my side it reproduces only on 29th level of D2 Plutonia. Have no idea why is it so, but it is so.

Test with music playback over General Midi (port 330 in dosbox).

Done by setup.exe in D2: General Midi, 330. Result: no music in game, but no hangs, no sig_6 on 29th level and other similar items.

Result is from user error:

1Above backtrace:
2CONFIG:Loading primary settings from config file /home/k_mikhail/.dosbox/dosbox-0.74.conf
3...
4ALSA:Can't subscribe to MIDI port (65:0) nor (17:0)
5MIDI:Opened device:none

http://askubuntu.com/questions/79944/dosbox-has-no-sound

Steps-to-reproduce: https://www.youtube.com/watch?v=2tY9VugtZh8

The similar one I have on 31th level of D2 Evilution.wad.

Dosbox 'general midi' is not configured.

If soundblaster music is preferred over general midi, then purchase a version of doom2 that can be updated with a fix for the music bug:
https://doomwiki.org/wiki/Versions_of_Doom_and_Doom_II#v1.7

And the web site for the patches:
http://www.doomworld.com/classicdoom/info/patches.php
"Note: there is -no- patch for Doom2 v1.666 dated 8/25/94."

Ok, thanks for help!