diff --git a/flake.lock b/flake.lock
deleted file mode 100644
index 7b5b54fef..000000000
--- a/flake.lock
+++ /dev/null
@@ -1,59 +0,0 @@
-{
-  "nodes": {
-    "flake-utils": {
-      "inputs": {
-        "systems": "systems"
-      },
-      "locked": {
-        "lastModified": 1731533236,
-        "narHash": "sha256-l0KFg5HjrsfsO/JpG+r7fRrqm12kzFHyUHqHCVpMMbI=",
-        "owner": "numtide",
-        "repo": "flake-utils",
-        "rev": "11707dc2f618dd54ca8739b309ec4fc024de578b",
-        "type": "github"
-      },
-      "original": {
-        "owner": "numtide",
-        "repo": "flake-utils",
-        "type": "github"
-      }
-    },
-    "nixpkgs": {
-      "locked": {
-        "lastModified": 1773110118,
-        "narHash": "sha256-mPAG8phMbCReKSiKAijjjd3v7uVcJOQ75gSjGJjt/Rk=",
-        "owner": "NixOS",
-        "repo": "nixpkgs",
-        "rev": "e607cb5360ff1234862ac9f8839522becb853bb9",
-        "type": "github"
-      },
-      "original": {
-        "id": "nixpkgs",
-        "type": "indirect"
-      }
-    },
-    "root": {
-      "inputs": {
-        "flake-utils": "flake-utils",
-        "nixpkgs": "nixpkgs"
-      }
-    },
-    "systems": {
-      "locked": {
-        "lastModified": 1681028828,
-        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
-        "owner": "nix-systems",
-        "repo": "default",
-        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
-        "type": "github"
-      },
-      "original": {
-        "owner": "nix-systems",
-        "repo": "default",
-        "type": "github"
-      }
-    }
-  },
-  "root": "root",
-  "version": 7
-}
diff --git a/flake.nix b/flake.nix
deleted file mode 100644
index b5ea1ff8b..000000000
--- a/flake.nix
+++ /dev/null
@@ -1,31 +0,0 @@
-{
-  description = "POKEHEARTGOLD decomp nix development shell";
-
-  inputs.flake-utils.url = "github:numtide/flake-utils";
-
-  outputs = { self, nixpkgs, flake-utils }:
-    flake-utils.lib.simpleFlake rec {
-      inherit self nixpkgs;
-      name = "pokeheartgold-shell";
-      # Native shell instead of an arm-cross shell so utilities are properly compiled for host
-      shell = { pkgs }: pkgs.mkShell {
-        inherit name;
-
-        nativeBuildInputs = [
-          pkgs.git
-          pkgs.wineWow64Packages.base # wine with both 32 and 64 bits support
-          pkgs.python3
-          pkgs.pkg-config
-          pkgs.pkgsCross.arm-embedded.stdenv.cc.bintools # binutils
-          pkgs.unzip
-          pkgs.p7zip
-          pkgs.clang-tools      # For the formatting
-          pkgs.libclang.python  # and the pre-commit hook
-        ];
-
-        buildInputs = [
-          pkgs.libpng
-        ];
-      };
-    };
-}
diff --git a/include/unk_02034B0C.h b/include/unk_02034B0C.h
index 7da303bc2..384073863 100644
--- a/include/unk_02034B0C.h
+++ b/include/unk_02034B0C.h
@@ -1,7 +1,7 @@
 #ifndef POKEHEARTGOLD_UNK_02034B0C_H
 #define POKEHEARTGOLD_UNK_02034B0C_H
 
-void sub_02034D8C();
+void sub_02034D8C(void);
 BOOL sub_02035650(void);
 
 #endif // POKEHEARTGOLD_UNK_02034B0C_H
diff --git a/src/overlay_13_thumb_1.c b/src/overlay_13_thumb_1.c
index 2d9cfdc97..22d816e1e 100644
--- a/src/overlay_13_thumb_1.c
+++ b/src/overlay_13_thumb_1.c
@@ -1,5 +1,7 @@
 #include "overlay_13_thumb_1.h"
 
+#include <nitro/hw/common/io_reg.h>
+
 #include "global.h"
 
 #include "overlay_00_thumb.h"
@@ -7,8 +9,8 @@
 #include "unk_02034B0C.h"
 
 void ov13_0221BA00(enum HeapID HeapID) {
-    for (int playerNo = 0; playerNo < 0x20; playerNo += 1) {
-        NNS_SndPlayerSetPlayerVolume(playerNo, 0x7F);
+    for (int playerNo = 0; playerNo < 32; playerNo++) {
+        NNS_SndPlayerSetPlayerVolume(playerNo, 127);
         NNS_SndPlayerSetPlayableSeqCount(playerNo, 1);
         NNS_SndPlayerSetAllocatableChannel(playerNo, 0);
     }
@@ -22,6 +24,6 @@ void ov13_0221BA00(enum HeapID HeapID) {
     Heap_Free(buffer);
     OS_RestoreInterrupts(interrupts);
 
-    u16 oldValue = *(vu16 *)0x04000208;
-    *(u16 *)0x04000208 = 1;
+    u16 oldValue = reg_OS_IME;
+    reg_OS_IME = 1;
 }