Forum rules Please be as descriptive as possible in your posts (list your hardware and operating system, the version of the source port you are using, any mods you are running and how they're being loaded, etc.)
This will help others to give you a solution!
Gtk-Message: 21:24:00.174: Failed to load module "canberra-gtk-module"
Zandronum 3.0.1 - 191013-1938 - SDL version
Compiled on Nov 3 2019
Using video driver x11
M_LoadDefaults: Load system defaults.
Gameinfo scan took 0 ms
W_Init: Init WADfiles.
adding /usr/games/zandronum/zandronum.pk3, 689 lumps
adding /home/nobody/.config/zandronum/DOOM2.WAD, 2919 lumps
I_Init: Setting up machine state.
CPU Vendor ID: GenuineIntel
Name: Intel(R) Pentium(R) CPU N3530 @ 2.16GHz
Family 6, Model 55, Stepping 8
Features: MMX SSE SSE2 SSE3 SSSE3 SSE4.1 SSE4.2
I_InitSound: Initializing FMOD
FMOD Sound System, copyright � Firelight Technologies Pty, Ltd., 1994-2009.
Loaded FMOD version 4.24.16
OSS could not be initialized. Trying ALSA.
free(): double free detected in tcache 2
Aborted (core dumped)
It seems similar to this bug report, though the distro is different. Can you check if this is the case, in particular with the debug compilation and the workaround?