diff --git a/pressure-vessel/runtime.c b/pressure-vessel/runtime.c
index 9f85a3fc436f11a884de7402ec59fcf663107704..396c5e26bce883d61a76c0a2bbc09e19ed66e585 100644
--- a/pressure-vessel/runtime.c
+++ b/pressure-vessel/runtime.c
@@ -4844,10 +4844,11 @@ pv_runtime_set_search_paths (PvRuntime *self,
   pv_environ_lock_env (container_env, "LD_LIBRARY_PATH", ld_library_path->str);
 }
 
-void
+gboolean
 pv_runtime_use_shared_sockets (PvRuntime *self,
                                FlatpakBwrap *bwrap,
-                               PvEnviron *container_env)
+                               PvEnviron *container_env,
+                               GError **error)
 {
   if (pv_environ_is_locked (container_env, "PULSE_SERVER")
       || self->is_flatpak_env)
@@ -4865,7 +4866,27 @@ pv_runtime_use_shared_sockets (PvRuntime *self,
                                        "/etc/asound.conf",
                                        NULL);
         }
+      else if (self->mutable_sysroot_fd >= 0)
+        {
+          /* In a Flatpak sub-sandbox, we can rely on the fact that
+           * Flatpak will mount each item in our copy of the runtime's
+           * usr/etc/ into /etc, including some that we would normally
+           * skip. */
+          if (!glnx_file_replace_contents_at (self->mutable_sysroot_fd,
+                                              "usr/etc/asound.conf",
+                                              (const guint8 *) alsa_config,
+                                              strlen (alsa_config),
+                                              GLNX_FILE_REPLACE_NODATASYNC,
+                                              NULL, error))
+            return FALSE;
+        }
+      else
+        {
+          g_warning ("Unable to configure libasound.so.2 to use PulseAudio");
+        }
     }
+
+  return TRUE;
 }
 
 static void
diff --git a/pressure-vessel/runtime.h b/pressure-vessel/runtime.h
index 151e59e2e4d522c7e56ad0475d0168e4bede16f7..1fe178e51d1f344945c6d9092460da350706b111 100644
--- a/pressure-vessel/runtime.h
+++ b/pressure-vessel/runtime.h
@@ -109,8 +109,9 @@ gboolean pv_runtime_garbage_collect_legacy (const char *variable_dir,
                                             const char *runtime_base,
                                             GError **error);
 
-void pv_runtime_use_shared_sockets (PvRuntime *self,
-                                    FlatpakBwrap *bwrap,
-                                    PvEnviron *container_env);
+gboolean pv_runtime_use_shared_sockets (PvRuntime *self,
+                                        FlatpakBwrap *bwrap,
+                                        PvEnviron *container_env,
+                                        GError **error);
 
 G_DEFINE_AUTOPTR_CLEANUP_FUNC (PvRuntime, g_object_unref)
diff --git a/pressure-vessel/wrap.c b/pressure-vessel/wrap.c
index ba37233a7ed98402efbbbca77801f7f9f657c4fe..f46a44d6bdbb1e2bf2da440754422cc7927e46cd 100644
--- a/pressure-vessel/wrap.c
+++ b/pressure-vessel/wrap.c
@@ -2418,7 +2418,11 @@ main (int argc,
                            is_flatpak_env);
 
   if (runtime != NULL)
-    pv_runtime_use_shared_sockets (runtime, bwrap, container_env);
+    {
+      if (!pv_runtime_use_shared_sockets (runtime, bwrap, container_env,
+                                          error))
+        goto out;
+    }
 
   if (is_flatpak_env)
     {