diff --git a/lib/make/mb_openmsx.mk b/lib/make/mb_openmsx.mk
index bd9c2d0..3bd145d 100644
--- a/lib/make/mb_openmsx.mk
+++ b/lib/make/mb_openmsx.mk
@@ -15,8 +15,9 @@ MB_OPENMSX_THROTTLE     ?= off
 MB_OPENMSX_RENDERER     ?=
 MB_OPENMSX_CTLCACHE     ?= $(MB_CACHE)/omsxctl
 MB_OPENMSX_SAVE_ON_EXIT ?= off
+MB_OPENMSX_SOUND_DRIVER ?= null
 
-# TODO: create openMSX issue to control extensions from the command line.
+# TODO: create openMSX issue to clean share: https://github.com/openMSX/openMSX/issues/1672
 define _mb_openmsx_setup
 	$(if $(wildcard $(MB_OPENMSX_CTLCACHE)),,$(call mb_mkdir,$(MB_OPENMSX_CTLCACHE)))
 	$(call mb_msxhub_file,$(MB_OPENMSX_CTLCACHE),OMSXCTL/1.0-1/get/OMSXCTL/omsxctl.tcl)
@@ -36,6 +37,7 @@ define _mb_openmsx_run
 	SCALE_FACTOR=$(MB_OPENMSX_SCALE_FACTOR) \
 	SPEED=$(MB_OPENMSX_SPEED) \
 	SAVE_SETTINGS_ON_EXIT=$(MB_OPENMSX_SAVE_ON_EXIT) \
+	SOUND_DRIVER=$(MB_OPENMSX_SOUND_DRIVER) \
 	RENDERER=$(MB_OPENMSX_RENDERER) \
 	THROTTLE=$(MB_OPENMSX_THROTTLE) \
 	$(PATH_OPENMSX)/openmsx \
diff --git a/lib/openmsx/boot_env.tcl b/lib/openmsx/boot_env.tcl
index 70edb9b..ec3da45 100644
--- a/lib/openmsx/boot_env.tcl
+++ b/lib/openmsx/boot_env.tcl
@@ -32,6 +32,13 @@ if {[info exists ::env(SAVE_SETTINGS_ON_EXIT)] && ([string trim $::env(SAVE_SETT
 	}
 }
 
+if {[info exists ::env(SOUND_DRIVER)] && ([string trim $::env(SOUND_DRIVER)] != "")} {
+	if {[catch {set sound_driver [string trim $::env(SOUND_DRIVER)]} err_msg]} {
+		puts stderr "error: env.SOUND_DRIVER value $err_msg"
+		exit 1
+	}
+}
+
 if {[info exists ::env(RENDERER)] && ([string trim $::env(RENDERER)] != "")} {
 	if {[catch {set renderer [string trim $::env(RENDERER)]} err_msg]} {
 		puts stderr "error: env.RENDERER value $err_msg"