From 670f0bb0c8a0d6dcd8ee858ffbd6b001d1da5131 Mon Sep 17 00:00:00 2001
From: Stenzek <stenzek@gmail.com>
Date: Sat, 17 Oct 2026 18:21:55 +1000
Subject: [PATCH] SPU: Sync pending samples on ENDX reads and manual RAM writes

---
 src/core/spu.cpp | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/core/spu.cpp b/src/core/spu.cpp
index bc0051819..56f35f234 100644
--- a/src/core/spu.cpp
+++ b/src/core/spu.cpp
@@ -785,9 +785,11 @@ u16 SPU::ReadRegister(u32 offset)
       return Truncate16(s_state.reverb_on_register >> 16);
 
     case 0x1F801D9C - SPU_BASE:
+      GeneratePendingSamples();
       return Truncate16(s_state.endx_register);
 
     case 0x1F801D9E - SPU_BASE:
+      GeneratePendingSamples();
       return Truncate16(s_state.endx_register >> 16);
 
     case 0x1F801DA2 - SPU_BASE:
@@ -1478,6 +1480,9 @@ void SPU::ManualTransferWrite(u16 value)
       ExecuteTransfer(nullptr, std::numeric_limits<s32>::max());
   }
 
+  // Pending samples need to read the old data.
+  InternalGeneratePendingSamples();
+
   std::memcpy(&s_ram[s_state.transfer_address], &value, sizeof(u16));
   s_state.transfer_address = (s_state.transfer_address + sizeof(u16)) & RAM_MASK;