diff --git a/Core/debugger.c b/Core/debugger.c
index fd292b7..b809262 100644
--- a/Core/debugger.c
+++ b/Core/debugger.c
@@ -1524,7 +1524,7 @@ static bool lcd(GB_gameboy_t *gb, char *arguments, char *modifiers, const debugg
     else if (gb->display_state == 7 || gb->display_state == 8) {
         GB_log(gb, "Reading OAM data (%d/40)\n", gb->display_state == 8? gb->oam_search_index : 0);
     }
-    else if (gb->display_state <= 3 || gb->display_state == 24) {
+    else if (gb->display_state <= 3 || gb->display_state == 24 || gb->display_state == 31) {
         GB_log(gb, "Glitched line 0 (%d cycles to next event)\n", -gb->display_cycles / 2);
     }
     else if (gb->mode_for_interrupt == 3) {
diff --git a/Core/display.c b/Core/display.c
index 6141e53..05a45b7 100644
--- a/Core/display.c
+++ b/Core/display.c
@@ -304,6 +304,7 @@ void GB_lcd_off(GB_gameboy_t *gb)
     gb->vram_read_blocked = false;
     gb->oam_write_blocked = false;
     gb->vram_write_blocked = false;
+    gb->cgb_palettes_blocked = false;
     
     /* Reset window rendering state */
     gb->wy_diff = 0;
@@ -586,6 +587,13 @@ void GB_display_run(GB_gameboy_t *gb, uint8_t cycles)
         GB_STATE(gb, display, 28);
         GB_STATE(gb, display, 29);
         GB_STATE(gb, display, 30);
+        GB_STATE(gb, display, 31);
+        GB_STATE(gb, display, 32);
+        GB_STATE(gb, display, 33);
+        GB_STATE(gb, display, 34);
+        GB_STATE(gb, display, 35);
+        GB_STATE(gb, display, 36);
+
     }
     
     if (!(gb->io_registers[GB_IO_LCDC] & 0x80)) {
@@ -610,23 +618,30 @@ void GB_display_run(GB_gameboy_t *gb, uint8_t cycles)
     gb->vram_read_blocked = false;
     gb->oam_write_blocked = false;
     gb->vram_write_blocked = false;
-    gb->cycles_for_line = MODE2_LENGTH - 2;
+    gb->cgb_palettes_blocked = false;
+    gb->cycles_for_line = MODE2_LENGTH - 4;
     GB_STAT_update(gb);
-    GB_SLEEP(gb, display, 2, MODE2_LENGTH - 2);
+    GB_SLEEP(gb, display, 2, MODE2_LENGTH - 4);
+    
+    gb->oam_write_blocked = true;
+    gb->cycles_for_line += 2;
+    GB_STAT_update(gb);
+    GB_SLEEP(gb, display, 34, 2);
     
     gb->io_registers[GB_IO_STAT] &= ~3;
     gb->io_registers[GB_IO_STAT] |= 3;
     gb->mode_for_interrupt = 3;
     gb->oam_read_blocked = true;
-    gb->vram_read_blocked = !GB_is_cgb(gb);
-    gb->oam_write_blocked = true;
-    gb->vram_write_blocked = !GB_is_cgb(gb);
+    gb->vram_read_blocked = !GB_is_cgb(gb) || gb->cgb_double_speed;
+    gb->vram_write_blocked = !GB_is_cgb(gb) || gb->cgb_double_speed;
+    gb->cgb_palettes_blocked = !GB_is_cgb(gb);
     GB_STAT_update(gb);
     
     gb->cycles_for_line += 2;
     GB_SLEEP(gb, display, 24, 2);
     gb->vram_read_blocked = true;
     gb->vram_write_blocked = true;
+    gb->cgb_palettes_blocked = true;
     
     /* TODO: How does the window affect this line? */
     gb->cycles_for_line += MODE3_LENGTH + (gb->io_registers[GB_IO_SCX] & 7) - 2;
@@ -650,6 +665,10 @@ void GB_display_run(GB_gameboy_t *gb, uint8_t cycles)
     gb->oam_write_blocked = false;
     gb->vram_write_blocked = false;
     
+    gb->cycles_for_line += 2;
+    GB_SLEEP(gb, display, 31, 2);
+    gb->cgb_palettes_blocked = false;
+    
     GB_STAT_update(gb);
     /* Mode 0 is shorter in the very first line */
     GB_SLEEP(gb, display, 5, LINE_LENGTH - gb->cycles_for_line - 8);
@@ -659,9 +678,13 @@ void GB_display_run(GB_gameboy_t *gb, uint8_t cycles)
     while (true) {
         /* Lines 0 - 143 */
         for (; gb->current_line < LINES; gb->current_line++) {
-            gb->oam_write_blocked = GB_is_cgb(gb);
+            gb->oam_write_blocked = GB_is_cgb(gb) && !gb->cgb_double_speed;
             gb->accessed_oam_row = 0;
-            GB_SLEEP(gb, display, 6, 3);
+            
+            GB_SLEEP(gb, display, 35, 2);
+            gb->oam_write_blocked = GB_is_cgb(gb);
+            
+            GB_SLEEP(gb, display, 6, 1);
             gb->io_registers[GB_IO_LY] = gb->current_line;
             gb->oam_read_blocked = true;
             gb->ly_for_comparison = gb->current_line? -1 : 0;
@@ -702,6 +725,7 @@ void GB_display_run(GB_gameboy_t *gb, uint8_t cycles)
                 if (gb->oam_search_index == 37) {
                     gb->vram_read_blocked = !GB_is_cgb(gb);
                     gb->vram_write_blocked = false;
+                    gb->cgb_palettes_blocked = false;
                     gb->oam_write_blocked = GB_is_cgb(gb);
                     GB_STAT_update(gb);
                 }
@@ -712,6 +736,7 @@ void GB_display_run(GB_gameboy_t *gb, uint8_t cycles)
             gb->mode_for_interrupt = 3;
             gb->vram_read_blocked = true;
             gb->vram_write_blocked = true;
+            gb->cgb_palettes_blocked = false;
             gb->oam_write_blocked = true;
             GB_STAT_update(gb);
 
@@ -725,13 +750,18 @@ void GB_display_run(GB_gameboy_t *gb, uint8_t cycles)
             gb->fetcher_x = ((gb->io_registers[GB_IO_SCX]) / 8) & 0x1f;
             gb->extra_penalty_for_sprite_at_0 = (gb->io_registers[GB_IO_SCX] & 7);
             
-            uint8_t idle_cycles = 5;
+            uint8_t idle_cycles = 3;
             if (GB_is_cgb(gb) && gb->model <= GB_MODEL_CGB_C) {
-                idle_cycles = 4;
+                idle_cycles = 2;
             }
             gb->cycles_for_line += idle_cycles;
             GB_SLEEP(gb, display, 10, idle_cycles);
+            
+            gb->cgb_palettes_blocked = true;
+            gb->cycles_for_line += 2;
+            GB_SLEEP(gb, display, 32, 2);
 
+            
             /* The actual rendering cycle */
             gb->fetcher_state = 0;
             gb->bg_fifo_paused = false;
@@ -848,9 +878,16 @@ void GB_display_run(GB_gameboy_t *gb, uint8_t cycles)
             GB_STAT_update(gb);
 
             /* Todo: Measure this value */
+            gb->cycles_for_line += 2;
+            GB_SLEEP(gb, display, 33, 2);
+            gb->cgb_palettes_blocked = !gb->cgb_double_speed;
             
-            gb->cycles_for_line += 12;
-            GB_SLEEP(gb, display, 25, 12);
+            gb->cycles_for_line += 2;
+            GB_SLEEP(gb, display, 36, 2);
+            gb->cgb_palettes_blocked = false;
+            
+            gb->cycles_for_line += 8;
+            GB_SLEEP(gb, display, 25, 8);
             
             if (gb->hdma_on_hblank) {
                 gb->hdma_starting = true;
diff --git a/Core/gb.h b/Core/gb.h
index e37a159..9dea4ef 100644
--- a/Core/gb.h
+++ b/Core/gb.h
@@ -465,6 +465,7 @@ struct GB_gameboy_internal_s {
         uint8_t extra_penalty_for_sprite_at_0;
         uint8_t mode_for_interrupt;
         bool lyc_interrupt_line;
+        bool cgb_palettes_blocked;
     );
 
     /* Unsaved data. This includes all pointers, as well as everything that shouldn't be on a save state */
diff --git a/Core/memory.c b/Core/memory.c
index 39f358e..262fc4d 100644
--- a/Core/memory.c
+++ b/Core/memory.c
@@ -197,7 +197,7 @@ static uint8_t read_high_memory(GB_gameboy_t *gb, uint16_t addr)
     }
 
     if (addr < 0xFF00) {
-        if (gb->oam_write_blocked) {
+        if (gb->oam_write_blocked && !GB_is_cgb(gb)) {
             GB_trigger_oam_bug_read(gb, addr);
             return 0xff;
         }
@@ -357,8 +357,7 @@ static uint8_t read_high_memory(GB_gameboy_t *gb, uint16_t addr)
                 if (!gb->cgb_mode && gb->boot_rom_finished) {
                     return 0xFF;
                 }
-                /* TODO: Verify actual access timing */
-                if (gb->vram_read_blocked) {
+                if (gb->cgb_palettes_blocked) {
                     return 0xFF;
                 }
                 uint8_t index_reg = (addr & 0xFF) - 1;
@@ -793,8 +792,7 @@ static void write_high_memory(GB_gameboy_t *gb, uint16_t addr, uint8_t value)
                        is required. */
                     return;
                 }
-                /* TODO: Verify actual access timing */
-                if (gb->vram_write_blocked) {
+                if (gb->cgb_palettes_blocked) {
                     return;
                 }
                 uint8_t index_reg = (addr & 0xFF) - 1;