diff --git a/src/emu/sound/ymz280b.c b/src/emu/sound/ymz280b.c
index 8f6360474f1..94469331575 100644
--- a/src/emu/sound/ymz280b.c
+++ b/src/emu/sound/ymz280b.c
@@ -607,9 +607,10 @@ void ymz280b_device::device_start()
 	save_item(NAME(m_irq_enable));
 	save_item(NAME(m_keyon_enable));
 	save_item(NAME(m_ext_mem_enable));
-	save_item(NAME(m_rom_readback_addr));
-	save_item(NAME(m_rom_addr_hi));
-	save_item(NAME(m_rom_addr_mid));
+	save_item(NAME(m_ext_mem_address));
+	save_item(NAME(m_ext_readlatch));
+	save_item(NAME(m_ext_mem_address_hi));
+	save_item(NAME(m_ext_mem_address_mid));
 	for (int j = 0; j < 8; j++)
 	{
 		save_item(NAME(m_voice[j].playing), j);
@@ -657,7 +658,7 @@ void ymz280b_device::device_reset()
 
 	m_current_register = 0;
 	m_status_register = 0;
-	m_rom_readback_addr = 0;
+	m_ext_mem_address = 0;
 
 	/* clear other voice parameters */
 	for (int i = 0; i < 8; i++)
@@ -808,25 +809,25 @@ void ymz280b_device::write_to_register(int data)
 				break;
 
 			case 0x84:      /* ROM readback / RAM write (high) */
-				m_rom_addr_hi = data << 16;
+				m_ext_mem_address_hi = data << 16;
 				break;
 
 			case 0x85:      /* ROM readback / RAM write (middle) */
-				m_rom_addr_mid = data << 8;
+				m_ext_mem_address_mid = data << 8;
 				break;
 
 			case 0x86:      /* ROM readback / RAM write (low) -> update latch */
-				m_rom_readback_addr = m_rom_addr_hi | m_rom_addr_mid | data;
+				m_ext_mem_address = m_ext_mem_address_hi | m_ext_mem_address_mid | data;
 				break;
 
 			case 0x87:      /* RAM write */
 				if (m_ext_mem_enable)
 				{
+					m_ext_mem_address = (m_ext_mem_address + 1) & 0xffffff;
 					if (!m_ext_write_handler.isnull())
-						m_ext_write_handler(m_rom_readback_addr, data);
+						m_ext_write_handler(m_ext_mem_address, data);
 					else
-						logerror("YMZ280B attempted RAM write to %X\n", m_rom_readback_addr);
-					m_rom_readback_addr = (m_rom_readback_addr + 1) & 0xffffff;
+						logerror("YMZ280B attempted RAM write to %X\n", m_ext_mem_address);
 				}
 				break;
 
@@ -908,9 +909,10 @@ READ8_MEMBER( ymz280b_device::read )
 			return 0xff;
 
 		/* read from external memory */
-		UINT8 result = ymz280b_read_memory(m_rom_readback_addr);
-		m_rom_readback_addr = (m_rom_readback_addr + 1) & 0xffffff;
-		return result;
+		UINT8 ret = m_ext_readlatch;
+		m_ext_readlatch = ymz280b_read_memory(m_ext_mem_address);
+		m_ext_mem_address = (m_ext_mem_address + 1) & 0xffffff;
+		return ret;
 	}
 	else
 		return compute_status();
@@ -943,9 +945,10 @@ ymz280b_device::ymz280b_device(const machine_config &mconfig, const char *tag, d
 		m_irq_enable(0),
 		m_keyon_enable(0),
 		m_ext_mem_enable(0),
-		m_rom_addr_hi(0),
-		m_rom_addr_mid(0),
-		m_rom_readback_addr(0),
+		m_ext_mem_address_hi(0),
+		m_ext_mem_address_mid(0),
+		m_ext_mem_address(0),
+		m_ext_readlatch(0),
 		m_irq_handler(*this),
 		m_ext_read_handler(*this),
 		m_ext_write_handler(*this)
diff --git a/src/emu/sound/ymz280b.h b/src/emu/sound/ymz280b.h
index d1d4bab316a..656ed30ec90 100644
--- a/src/emu/sound/ymz280b.h
+++ b/src/emu/sound/ymz280b.h
@@ -105,9 +105,10 @@ private:
 	UINT8 m_irq_enable;               /* current IRQ enable */
 	UINT8 m_keyon_enable;             /* key on enable */
 	UINT8 m_ext_mem_enable;           /* external memory enable */
-	UINT32 m_rom_addr_hi;
-	UINT32 m_rom_addr_mid;
-	UINT32 m_rom_readback_addr;       /* where the CPU can read the ROM */
+	UINT8 m_ext_readlatch;            /* external memory prefetched data */
+	UINT32 m_ext_mem_address_hi;
+	UINT32 m_ext_mem_address_mid;
+	UINT32 m_ext_mem_address;         /* where the CPU can read the ROM */
 
 	devcb2_write_line m_irq_handler;  /* IRQ callback */
 	devcb2_read8 m_ext_read_handler;  /* external RAM read handler */
diff --git a/src/mame/drivers/firebeat.c b/src/mame/drivers/firebeat.c
index c66e976929c..0f275206769 100644
--- a/src/mame/drivers/firebeat.c
+++ b/src/mame/drivers/firebeat.c
@@ -1876,12 +1876,6 @@ ADDRESS_MAP_END
 
 READ8_MEMBER(firebeat_state::soundram_r)
 {
-	// HACK: firebeat expects first read after setting the address to be dummy.  fixes "YMZ test".
-	if (offset > 0)
-	{
-		offset--;
-	}
-
 	if (offset < 0x200000)
 	{
 		return m_flash[1]->read(offset & 0x1fffff);