diff --git a/src/mame/drivers/segas16b.cpp b/src/mame/drivers/segas16b.cpp
index b62a4f1ebe4..9894c416e1c 100644
--- a/src/mame/drivers/segas16b.cpp
+++ b/src/mame/drivers/segas16b.cpp
@@ -1354,27 +1354,6 @@ void segas16b_state::altbeasj_i8751_sim()
 }
 
 
-
-//-------------------------------------------------
-//  ddux_i8751_sim - simulate the I8751
-//  from Dynamite Dux
-//-------------------------------------------------
-
-void segas16b_state::ddux_i8751_sim()
-{
-	// signal a VBLANK to the main CPU
-	m_maincpu->set_input_line(4, HOLD_LINE);
-
-	// process any new sound data
-	uint16_t temp = m_workram[0x0bd0/2];
-	if ((temp & 0xff00) != 0x0000)
-	{
-		address_space &space = m_maincpu->space(AS_PROGRAM);
-		m_mapper->write(space, 0x03, temp >> 8);
-		m_workram[0x0bd0/2] = temp & 0x00ff;
-	}
-}
-
 //-------------------------------------------------
 //  tturf_i8751_sim - simulate the I8751
 //  from Tough Turf
@@ -6203,7 +6182,7 @@ ROM_START( ddux1 )
 	ROM_LOAD( "epr-11916.a10", 0x0000, 0x8000, CRC(7ab541cf) SHA1(feb88022ca1796d020e53e95ad345159bd415530) )
 
 	ROM_REGION( 0x1000, "mcu", 0 )  // Intel i8751 protection MCU
-	ROM_LOAD( "317-0095.c2", 0x00000, 0x1000, NO_DUMP )
+	ROM_LOAD( "317-0095.c2", 0x00000, 0x1000, CRC(b06b4ca7) SHA1(563807dd8194179e25a2186f3572fb3738537c33) )
 ROM_END
 
 
@@ -9392,12 +9371,6 @@ void segas16b_state::init_altbeas4_5521()
 	downcast<mc8123_device &>(*m_soundcpu).decode(memregion("soundcpu")->base(), m_sound_decrypted_opcodes, 0x8000);
 }
 
-void segas16b_state::init_ddux_5704()
-{
-	init_generic_5704();
-	m_i8751_vblank_hook = i8751_sim_delegate(&segas16b_state::ddux_i8751_sim, this);
-}
-
 void segas16b_state::init_dunkshot_5358_small()
 {
 	init_generic_5358_small();
@@ -9551,7 +9524,7 @@ GAME( 1991, cottonja,   cotton,   system16b_fd1094,      cotton,   segas16b_stat
 
 GAME( 1988, ddux,       0,        system16b_fd1094,      ddux,     segas16b_state, init_generic_5521,       ROT0,   "Sega", "Dynamite Dux (set 3, World) (FD1094 317-0096)", 0 )
 GAME( 1988, dduxj,      ddux,     system16b_fd1094,      ddux,     segas16b_state, init_generic_5521,       ROT0,   "Sega", "Dynamite Dux (set 2, Japan) (FD1094 317-0094)", 0 )
-GAME( 1988, ddux1,      ddux,     system16b_i8751,       ddux,     segas16b_state, init_ddux_5704,          ROT0,   "Sega", "Dynamite Dux (set 1) (8751 317-0095)", 0 )
+GAME( 1988, ddux1,      ddux,     system16b_i8751,       ddux,     segas16b_state, init_generic_5704,       ROT0,   "Sega", "Dynamite Dux (set 1) (8751 317-0095)", 0 )
 
 GAME( 1987, dunkshot,   0,        system16b_fd1089a,     dunkshot,  segas16b_state, init_dunkshot_5358_small,ROT0,   "Sega", "Dunk Shot (Rev C, FD1089A 317-0022)", 0 )
 GAME( 1987, dunkshota,  dunkshot, system16b_fd1089a,     dunkshot,  segas16b_state, init_dunkshot_5358_small,ROT0,   "Sega", "Dunk Shot (Rev A, FD1089A 317-0022)", 0 )
diff --git a/src/mame/includes/segas16b.h b/src/mame/includes/segas16b.h
index f709f332871..16fe92e61ca 100644
--- a/src/mame/includes/segas16b.h
+++ b/src/mame/includes/segas16b.h
@@ -111,7 +111,6 @@ public:
 	void init_sdi_5358_small();
 	void init_fpointbla();
 	void init_altbeasj_5521();
-	void init_ddux_5704();
 	void init_snapper();
 	void init_shinobi4_5521();
 	void init_defense_5358_small();
@@ -226,7 +225,6 @@ protected:
 	// i8751 simulations
 	void altbeast_common_i8751_sim(offs_t soundoffs, offs_t inputoffs, int alt_bank);
 	void altbeasj_i8751_sim();
-	void ddux_i8751_sim();
 	void tturf_i8751_sim();
 	void wb3_i8751_sim();