This is on Trixie RC2, current as of July 8th, 2025.
-------------------------------------------------
[1]    139148 IOT instruction  pavucontrol
---------------------------------------------------

I recompiled on this machine (apt-get build-dep pavucontrol; cd
pavucontrol-6.1; fakeroot ./debian/rules binary), but the results were
unchanged, so this is at least some reproducability.

Running under strace had this output at the tail end
 ================================================================================
openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 29
fstat(29, {st_mode=S_IFREG|0644, st_size=49698, ...}) = 0
mmap(NULL, 49698, PROT_READ, MAP_PRIVATE, 29, 0) = 0x7f18a7e48000
close(29)                               = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libGLX.so.1", O_RDONLY|O_CLOEXEC) =
-1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/x86_64-linux-gnu/libGLX.so.1",
O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/lib/libGLX.so.1", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No
such file or directory)
openat(AT_FDCWD, "/usr/lib/libGLX.so.1", O_RDONLY|O_CLOEXEC) = -1 ENOENT
(No such file or directory)
munmap(0x7f18a7e48000, 49698)           = 0
openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 29
fstat(29, {st_mode=S_IFREG|0644, st_size=49698, ...}) = 0
mmap(NULL, 49698, PROT_READ, MAP_PRIVATE, 29, 0) = 0x7f18a7e48000
close(29)                               = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libGL.so.1", O_RDONLY|O_CLOEXEC) =
29
read(29,
"\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\0\0\0\0\0\0\0\0"..., 832) =
832
fstat(29, {st_mode=S_IFREG|0644, st_size=542880, ...}) = 0
close(29)                               = 0
munmap(0x7f18a7e48000, 49698)           = 0
getpid()                                = 131317
getpid()                                = 131317
getpid()                                = 131317
openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 29
fstat(29, {st_mode=S_IFREG|0644, st_size=49698, ...}) = 0
mmap(NULL, 49698, PROT_READ, MAP_PRIVATE, 29, 0) = 0x7f18a7e48000
close(29)                               = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libGLESv2.so.2",
O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/x86_64-linux-gnu/libGLESv2.so.2",
O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/lib/libGLESv2.so.2", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No
such file or directory)
openat(AT_FDCWD, "/usr/lib/libGLESv2.so.2", O_RDONLY|O_CLOEXEC) = -1 ENOENT
(No such file or directory)
munmap(0x7f18a7e48000, 49698)           = 0
write(2, "Couldn't open libGLESv2.so.2: li"..., 104Couldn't open
libGLESv2.so.2: libGLESv2.so.2: cannot open shared object file: No such
file or directory
) = 104
gettid()                                = 131317
getpid()                                = 131317
tgkill(131317, 131317, SIGABRT)         = 0
--- SIGABRT {si_signo=SIGABRT, si_code=SI_TKILL, si_pid=131317,
si_uid=1000} ---
+++ killed by SIGABRT +++
================================================================================

Hi,

        After today’s update, sound is now working, as is
 pavucontrol. However, I can’t point to a package upgrade that would
 have fixed the issue. I am still  on 6.12.33 (not yet updated to .35),
 and I don’t see any updates to  pavucontrol or libgles2 (still at
 1.7.0-1+b2), /var/log/dpkg.log does not record any movement.

        I do have nvidia audio, and I moved from nvidia-dkms to
 nvidia-open-dkms, and refreshed the nvidia modules. I wish I had taken
 a snapshot of the files associated with libgles2 before things fixed
 themselves.

        Manoj