diff --git a/.gitmodules b/.gitmodules
index 6efbe97a..7998285c 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +1,4 @@
 [submodule "rpi-rgb-led-matrix-master"]
 	path = rpi-rgb-led-matrix-master
 	url = https://github.com/hzeller/rpi-rgb-led-matrix.git
+	branch = master
diff --git a/config/config.template.json b/config/config.template.json
index 8eb664e1..b55220ef 100644
--- a/config/config.template.json
+++ b/config/config.template.json
@@ -112,7 +112,8 @@
             "limit_refresh_rate_hz": 100
         },
         "runtime": {
-            "gpio_slowdown": 3
+            "gpio_slowdown": 3,
+            "rp1_rio": 0
         },
         "display_durations": {},
         "use_short_date_format": true,
diff --git a/first_time_install.sh b/first_time_install.sh
index 2c46ed7f..f2b777ba 100644
--- a/first_time_install.sh
+++ b/first_time_install.sh
@@ -795,7 +795,7 @@ else
         # Try to initialize submodule if .gitmodules exists
         if [ -f "$PROJECT_ROOT_DIR/.gitmodules" ] && grep -q "rpi-rgb-led-matrix" "$PROJECT_ROOT_DIR/.gitmodules"; then
             echo "Initializing rpi-rgb-led-matrix submodule..."
-            if ! git submodule update --init --recursive rpi-rgb-led-matrix-master 2>&1; then
+            if ! git submodule update --init --remote --recursive rpi-rgb-led-matrix-master 2>&1; then
                 echo "⚠ Submodule init failed, cloning directly from GitHub..."
                 git clone https://github.com/hzeller/rpi-rgb-led-matrix.git rpi-rgb-led-matrix-master
             fi
@@ -814,7 +814,7 @@ else
             cd "$PROJECT_ROOT_DIR"
             rm -rf rpi-rgb-led-matrix-master
             if [ -f "$PROJECT_ROOT_DIR/.gitmodules" ] && grep -q "rpi-rgb-led-matrix" "$PROJECT_ROOT_DIR/.gitmodules"; then
-                git submodule update --init --recursive rpi-rgb-led-matrix-master
+                git submodule update --init --remote --recursive rpi-rgb-led-matrix-master
             else
                 git clone https://github.com/hzeller/rpi-rgb-led-matrix.git rpi-rgb-led-matrix-master
             fi
diff --git a/rpi-rgb-led-matrix-master b/rpi-rgb-led-matrix-master
index 2cfff2a4..89072356 160000
--- a/rpi-rgb-led-matrix-master
+++ b/rpi-rgb-led-matrix-master
@@ -1 +1 @@
-Subproject commit 2cfff2a4b14825795e195d2bf3a9b2ef2ac93446
+Subproject commit 89072356305e272c2b1af32b8377a274df3d6d9f
diff --git a/src/display_manager.py b/src/display_manager.py
index 43433582..15538866 100644
--- a/src/display_manager.py
+++ b/src/display_manager.py
@@ -100,6 +100,10 @@ class DisplayManager:
                 options.pwm_dither_bits = hardware_config.get('pwm_dither_bits')
             if 'inverse_colors' in hardware_config:
                 options.inverse_colors = hardware_config.get('inverse_colors')
+            # Pi 5 only: 0=PIO/RP1 coprocessor (default, less CPU),
+            # 1=RIO/Registered IO (faster; gpio_slowdown effect is inverted in this mode)
+            if 'rp1_rio' in runtime_config:
+                options.rp1_rio = runtime_config.get('rp1_rio')
             
             logger.info(f"Initializing RGB Matrix with settings: rows={options.rows}, cols={options.cols}, chain_length={options.chain_length}, parallel={options.parallel}, hardware_mapping={options.hardware_mapping}")