I am sponsoring the fix for this. debdiff is attached.
diff -Nru vpb-driver-4.2.61/debian/changelog vpb-driver-4.2.61/debian/changelog
--- vpb-driver-4.2.61/debian/changelog 2022-12-10 00:42:50.000000000 +0100
+++ vpb-driver-4.2.61/debian/changelog 2022-12-10 10:49:17.000000000 +0100
@@ -1,3 +1,10 @@
+vpb-driver (4.2.61-1.4) unstable; urgency=medium
+
+ * Non-maintainer upload.
+ * Fix ftbfs. (Closes: #1025831)
+
+ -- Bo YU <tsu.y...@gmail.com> Sat, 10 Dec 2022 17:49:17 +0800
+
vpb-driver (4.2.61-1.3) unstable; urgency=medium
* Non-maintainer upload
diff -Nru vpb-driver-4.2.61/debian/patches/fix-ftbfs-missing-pthread.patch
vpb-driver-4.2.61/debian/patches/fix-ftbfs-missing-pthread.patch
--- vpb-driver-4.2.61/debian/patches/fix-ftbfs-missing-pthread.patch
1970-01-01 01:00:00.000000000 +0100
+++ vpb-driver-4.2.61/debian/patches/fix-ftbfs-missing-pthread.patch
2022-12-10 10:49:17.000000000 +0100
@@ -0,0 +1,49 @@
+Description: fix ftbfs due to missing pthread
+Author: Bo YU <tsu.y...@gmail.com>
+Bug: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1025831
+Forwarded: no
+Last-Update: 2022-12-10
+---
+This patch header follows DEP-3: http://dep.debian.net/deps/dep3/
+--- a/include/vt/tonegen.h
++++ b/include/vt/tonegen.h
+@@ -35,6 +35,7 @@
+ #include <vector>
+ #include <string>
+ #include <stdint.h>
++#include <pthread.h>
+
+
+ //XXX this might be better as a generic tool in some other file, but for
+--- a/src/utils/playwav.cpp
++++ b/src/utils/playwav.cpp
+@@ -25,7 +25,7 @@
+
\*---------------------------------------------------------------------------*/
+
+ #include "vpbapi.h"
+-//#include "threads.h" // for billware
++#include "threads.h"
+
+ #include <cstdio>
+ #include <cstdlib>
+--- a/src/utils/tonegen.cpp
++++ b/src/utils/tonegen.cpp
+@@ -26,6 +26,7 @@
+
+ #include "vpbapi.h"
+ #include "kbhit.h"
++#include "threads.h"
+
+ #include <cstdio>
+ #include <cstdlib>
+--- a/src/utils/vpbecho.cpp
++++ b/src/utils/vpbecho.cpp
+@@ -34,7 +34,7 @@
+ #include "vpbapi.h"
+ #include "verbose.h"
+ #include "kbhit.h"
+-//#include "threads.h" // for billware
++#include "threads.h"
+
+ #include <cstdio>
+ #include <cstdlib>
diff -Nru vpb-driver-4.2.61/debian/patches/series
vpb-driver-4.2.61/debian/patches/series
--- vpb-driver-4.2.61/debian/patches/series 2022-12-10 00:42:50.000000000
+0100
+++ vpb-driver-4.2.61/debian/patches/series 2022-12-10 04:56:35.000000000
+0100
@@ -1 +1,2 @@
debian.patch
+fix-ftbfs-missing-pthread.patch
