diff --git a/include/mgba/core/map-cache.h b/include/mgba/core/map-cache.h
index 5d16287b4..22771459d 100644
--- a/include/mgba/core/map-cache.h
+++ b/include/mgba/core/map-cache.h
@@ -56,6 +56,7 @@ struct mMapCache {
 	mMapCacheSystemInfo sysConfig;
 
 	void (*mapParser)(struct mMapCache*, struct mMapCacheEntry* entry, void* vram);
+	void* context;
 };
 
 void mMapCacheInit(struct mMapCache* cache);
diff --git a/src/core/map-cache.c b/src/core/map-cache.c
index f818c7e2f..ed18979f6 100644
--- a/src/core/map-cache.c
+++ b/src/core/map-cache.c
@@ -132,21 +132,21 @@ static inline size_t _tileId(struct mMapCache* cache, unsigned x, unsigned y) {
 void mMapCacheCleanTile(struct mMapCache* cache, struct mMapCacheEntry* entry, unsigned x, unsigned y) {
 	size_t location = _tileId(cache, x, y);
 	struct mMapCacheEntry* status = &cache->status[location];
-	int paletteId = mMapCacheEntryFlagsGetPaletteId(status->flags);
 	const color_t* tile = NULL;
 	if (!mMapCacheEntryFlagsIsVramClean(status->flags)) {
 		status->flags = mMapCacheEntryFlagsFillVramClean(status->flags);
 		cache->mapParser(cache, status, &cache->vram[cache->mapStart + (location << mMapCacheSystemInfoGetMapAlign(cache->sysConfig))]);
-		tile = mTileCacheGetTileIfDirty(cache->tileCache, &status->tileStatus[paletteId], status->tileId + cache->tileStart, mMapCacheEntryFlagsGetPaletteId(status->flags));
-		if (!tile) {
-			tile = mTileCacheGetTile(cache->tileCache, status->tileId + cache->tileStart, mMapCacheEntryFlagsGetPaletteId(status->flags));
-		}
-	} else {
-		tile = mTileCacheGetTileIfDirty(cache->tileCache, &status->tileStatus[paletteId], status->tileId + cache->tileStart, mMapCacheEntryFlagsGetPaletteId(status->flags));
-		if (!tile && memcmp(status, &entry[location], sizeof(*entry)) == 0) {
+	}
+	unsigned tileId = status->tileId + cache->tileStart;
+	if (tileId >= mTileCacheSystemInfoGetMaxTiles(cache->tileCache->sysConfig)) {
+		tileId = 0;
+	}
+	tile = mTileCacheGetTileIfDirty(cache->tileCache, status->tileStatus, tileId, mMapCacheEntryFlagsGetPaletteId(status->flags));
+	if (!tile) {
+		if (mMapCacheEntryFlagsIsVramClean(status->flags) && memcmp(status, &entry[location], sizeof(*entry)) == 0) {
 			return;
 		}
-		tile = mTileCacheGetTile(cache->tileCache, status->tileId + cache->tileStart, mMapCacheEntryFlagsGetPaletteId(status->flags));
+		tile = mTileCacheGetTile(cache->tileCache, tileId, mMapCacheEntryFlagsGetPaletteId(status->flags));
 	}
 
 	size_t stride = 8 << mMapCacheSystemInfoGetTilesWide(cache->sysConfig);
@@ -161,7 +161,11 @@ bool mMapCacheCheckTile(struct mMapCache* cache, const struct mMapCacheEntry* en
 	int paletteId = mMapCacheEntryFlagsGetPaletteId(status->flags);
 	const color_t* tile = NULL;
 	if (mMapCacheEntryFlagsIsVramClean(status->flags) && memcmp(status, &entry[location], sizeof(*entry)) == 0) {
-		tile = mTileCacheGetTileIfDirty(cache->tileCache, &status->tileStatus[paletteId], status->tileId + cache->tileStart, mMapCacheEntryFlagsGetPaletteId(status->flags));
+		unsigned tileId = status->tileId + cache->tileStart;
+		if (tileId >= mTileCacheSystemInfoGetMaxTiles(cache->tileCache->sysConfig)) {
+			tileId = 0;
+		}
+		tile = mTileCacheGetTileIfDirty(cache->tileCache, &status->tileStatus[paletteId], tileId, mMapCacheEntryFlagsGetPaletteId(status->flags));
 		return !tile;
 	}
 	return false;
diff --git a/src/gba/renderers/cache-set.c b/src/gba/renderers/cache-set.c
index ddbeb0dfc..ce28d7e20 100644
--- a/src/gba/renderers/cache-set.c
+++ b/src/gba/renderers/cache-set.c
@@ -104,6 +104,7 @@ static void GBAVideoCacheWriteDISPCNT(struct mCacheSet* cache, uint16_t value) {
 
 static void GBAVideoCacheWriteBGCNT(struct mCacheSet* cache, size_t bg, uint16_t value) {
 	struct mMapCache* map = mMapCacheSetGetPointer(&cache->maps, bg);
+	map->context = (void*) (uintptr_t) value;
 
 	int tileStart = GBARegisterBGCNTGetCharBase(value) * 256;
 	bool p = GBARegisterBGCNTGet256Color(value);
@@ -145,6 +146,10 @@ void GBAVideoCacheWriteVideoRegister(struct mCacheSet* cache, uint32_t address,
 	switch (address) {
 	case REG_DISPCNT:
 		GBAVideoCacheWriteDISPCNT(cache, value);
+		GBAVideoCacheWriteBGCNT(cache, 0, (uint16_t) mMapCacheSetGetPointer(&cache->maps, 0)->context);
+		GBAVideoCacheWriteBGCNT(cache, 1, (uint16_t) mMapCacheSetGetPointer(&cache->maps, 1)->context);
+		GBAVideoCacheWriteBGCNT(cache, 2, (uint16_t) mMapCacheSetGetPointer(&cache->maps, 2)->context);
+		GBAVideoCacheWriteBGCNT(cache, 3, (uint16_t) mMapCacheSetGetPointer(&cache->maps, 3)->context);
 		break;
 	case REG_BG0CNT:
 		GBAVideoCacheWriteBGCNT(cache, 0, value);
diff --git a/src/platform/qt/MapView.cpp b/src/platform/qt/MapView.cpp
index 129bea3d8..4db7b1b8b 100644
--- a/src/platform/qt/MapView.cpp
+++ b/src/platform/qt/MapView.cpp
@@ -90,7 +90,7 @@ void MapView::updateTilesGBA(bool force) {
 		uchar* bgBits = m_rawMap.bits();
 		for (int j = 0; j < tilesH; ++j) {
 			for (int i = 0; i < tilesW; ++i) {
-				mMapCacheCleanTile(mapCache, &m_mapStatus[i + j * tilesW], i, j);
+				mMapCacheCleanTile(mapCache, m_mapStatus, i, j);
 			}
 			for (int i = 0; i < 8; ++i) {
 				memcpy(static_cast<void*>(&bgBits[tilesW * 32 * (i + j * 8)]), mMapCacheGetRow(mapCache, i + j * 8), tilesW * 32);
diff --git a/src/platform/qt/MapView.h b/src/platform/qt/MapView.h
index 7b9865ed3..7466cb038 100644
--- a/src/platform/qt/MapView.h
+++ b/src/platform/qt/MapView.h
@@ -40,7 +40,7 @@ private:
 	Ui::MapView m_ui;
 
 	std::shared_ptr<CoreController> m_controller;
-	mMapCacheEntry m_mapStatus[1024 * 1024] = {}; // TODO: Correct size
+	mMapCacheEntry m_mapStatus[128 * 128] = {}; // TODO: Correct size
 	int m_map = 0;
 	QImage m_rawMap;
 };