From 711a8aa6adf211b766880c21fbb542b3f35fbbe6 Mon Sep 17 00:00:00 2001
From: skidau <skidau@gmail.com>
Date: Tue, 30 Sep 2014 22:11:34 +1000
Subject: [PATCH] Fixed the step_size_bytes in the ADPCM Accelerator loop
 taking into account the varying number of bytes that ADPCM steps by.

---
 Source/Core/Core/DSP/DSPAccelerator.cpp     | 5 ++++-
 Source/Core/Core/HW/DSPHLE/UCodes/AXVoice.h | 7 +++++--
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/Source/Core/Core/DSP/DSPAccelerator.cpp b/Source/Core/Core/DSP/DSPAccelerator.cpp
index 5e9f1ca52b..7dad45caf6 100644
--- a/Source/Core/Core/DSP/DSPAccelerator.cpp
+++ b/Source/Core/Core/DSP/DSPAccelerator.cpp
@@ -122,8 +122,11 @@ u16 dsp_read_accelerator()
 	switch (g_dsp.ifx_regs[DSP_FORMAT])
 	{
 		case 0x00:  // ADPCM audio
+			if ((Address & 15) == 0)
+				step_size_bytes = 2;
+			else
+				step_size_bytes = 1;
 			val = ADPCM_Step(Address);
-			step_size_bytes = 2;
 			break;
 		case 0x0A:  // 16-bit PCM audio
 			val = (DSPHost::ReadHostMemory(Address * 2) << 8) | DSPHost::ReadHostMemory(Address * 2 + 1);
diff --git a/Source/Core/Core/HW/DSPHLE/UCodes/AXVoice.h b/Source/Core/Core/HW/DSPHLE/UCodes/AXVoice.h
index 070c82170a..d78d87e1a4 100644
--- a/Source/Core/Core/HW/DSPHLE/UCodes/AXVoice.h
+++ b/Source/Core/Core/HW/DSPHLE/UCodes/AXVoice.h
@@ -163,9 +163,13 @@ u16 AcceleratorGetSample()
 			if ((*acc_cur_addr & 15) == 0)
 			{
 				acc_pb->adpcm.pred_scale = DSP::ReadARAM((*acc_cur_addr & ~15) >> 1);
+				step_size_bytes = 2;
 				*acc_cur_addr += 2;
 			}
-
+			else
+			{
+				step_size_bytes = 1;
+			}
 			int scale = 1 << (acc_pb->adpcm.pred_scale & 0xF);
 			int coef_idx = (acc_pb->adpcm.pred_scale >> 4) & 0x7;
 
@@ -184,7 +188,6 @@ u16 AcceleratorGetSample()
 
 			acc_pb->adpcm.yn2 = acc_pb->adpcm.yn1;
 			acc_pb->adpcm.yn1 = val;
-			step_size_bytes = 2;
 			*acc_cur_addr += 1;
 			ret = val;
 			break;