diff --git a/builddtbo.sh b/builddtbo.sh
index 22c0046..e98800f 100755
--- a/builddtbo.sh
+++ b/builddtbo.sh
@@ -1,8 +1,9 @@
 #dtoverlay -r seeed-2mic-voicecard
+DTC_FLAGS="-b 0 -Wno-unit_address_vs_reg -I dts -O dtb"
 
-dtc -@ -I dts -O dtb -o seeed-2mic-voicecard.dtbo seeed-2mic-voicecard-overlay.dts
-dtc -@ -I dts -O dtb -o seeed-4mic-voicecard.dtbo seeed-4mic-voicecard-overlay.dts
-dtc -@ -I dts -O dtb -o seeed-8mic-voicecard.dtbo seeed-8mic-voicecard-overlay.dts
+dtc -@ $DTC_FLAGS -o seeed-2mic-voicecard.dtbo seeed-2mic-voicecard-overlay.dts
+dtc -@ $DTC_FLAGS -o seeed-4mic-voicecard.dtbo seeed-4mic-voicecard-overlay.dts
+dtc -@ $DTC_FLAGS -o seeed-8mic-voicecard.dtbo seeed-8mic-voicecard-overlay.dts
 
 # cp *.dtbo /boot/overlays
 # dtoverlay seeed-2mic-voicecard
diff --git a/install.sh b/install.sh
index 105d058..fe6408a 100755
--- a/install.sh
+++ b/install.sh
@@ -39,6 +39,7 @@ _VER_RUN=
 function get_kernel_version() {
   local ZIMAGE IMG_OFFSET
 
+  _VER_RUN=""
   [ -z "$_VER_RUN" ] && {
     ZIMAGE=/boot/kernel.img
     IMG_OFFSET=$(LC_ALL=C grep -abo $'\x1f\x8b\x08\x00' $ZIMAGE | head -n 1 | cut -d ':' -f 1)
@@ -173,6 +174,7 @@ git --git-dir=/etc/voicecard/.git --work-tree=/etc/voicecard/ commit  -m "origin
 cp seeed-voicecard /usr/bin/
 cp seeed-voicecard.service /lib/systemd/system/
 systemctl enable  seeed-voicecard.service 
+systemctl start   seeed-voicecard
 
 echo "------------------------------------------------------"
 echo "Please reboot your raspberry pi to apply all settings"
diff --git a/seeed-8mic-voicecard-overlay.dts b/seeed-8mic-voicecard-overlay.dts
index 800e07c..6d60469 100644
--- a/seeed-8mic-voicecard-overlay.dts
+++ b/seeed-8mic-voicecard-overlay.dts
@@ -26,13 +26,15 @@
 	fragment@2 {
 		target = <&gpio>;
 		__overlay__ {
-			spk_amp_and_irq_pins: speaker_amp_and_irq_pins {
+			spk_amp_pins: spk_pins {
 				brcm,pins = <17 22>;
 				brcm,function = <1 0>; /* out in */
+				brcm,pull = <0 0>;     /* -   - */
 			};
 			gpclk0_pins: gpclk0_pins {
 				brcm,pins = <4>;
 				brcm,function = <4>; /* alt func 0 */
+				brcm,pull = <0>;     /* - */
 			};
 		};
 	};
@@ -47,7 +49,7 @@
 			ac101: ac101@1a{
 				compatible = "x-power,ac101";
 				pinctrl-names = "default";
-				pinctrl-0 = <&spk_amp_and_irq_pins>,<&gpclk0_pins>;
+				pinctrl-0 = <&spk_amp_pins &gpclk0_pins>;
 				spk-amp-switch-gpios = <&gpio 17 0>;
 				switch-irq-gpios = <&gpio 22 0>;
 				reg = <0x1a>;
@@ -80,6 +82,8 @@
 			seeed-voice-card,name = "seeed-8mic-voicecard"; 
 			seeed-voice-card,channels-playback-override = <8>;
 			seeed-voice-card,channels-capture-override  = <8>;
+			#address-cells = <1>;
+			#size-cells = <0>;
 			status = "okay";
 
 			seeed-voice-card,dai-link@0 {
@@ -88,6 +92,7 @@
 				frame-master = <&codec0_dai>;
 				/* bitclock-inversion; */
 				/* frame-inversion; */
+				reg = <0>;
 
 				cpu {
 					sound-dai = <&i2s>;
diff --git a/seeed-8mic-voicecard.dtbo b/seeed-8mic-voicecard.dtbo
index 1976f6e..4ef515b 100644
Binary files a/seeed-8mic-voicecard.dtbo and b/seeed-8mic-voicecard.dtbo differ
diff --git a/seeed-voicecard b/seeed-voicecard
index 2818554..22e95b2 100755
--- a/seeed-voicecard
+++ b/seeed-voicecard
@@ -29,6 +29,56 @@ modprobe i2c-dev
 #enable spi interface
 dtparam spi=on
 
+_VER_RUN=
+function get_kernel_version() {
+    local ZIMAGE IMG_OFFSET
+
+    _VER_RUN=""
+    [ -z "$_VER_RUN" ] && {
+        ZIMAGE=/boot/kernel.img
+        IMG_OFFSET=$(LC_ALL=C grep -abo $'\x1f\x8b\x08\x00' $ZIMAGE | head -n 1 | cut -d ':' -f 1)
+        _VER_RUN=$(dd if=$ZIMAGE obs=64K ibs=4 skip=$(( IMG_OFFSET / 4)) | zcat | grep -a -m1 "Linux version" | strings | awk '{ print $3; }')
+    }
+    echo "$_VER_RUN"
+    return 0
+}
+
+CONFIG=/boot/config.txt
+get_overlay() {
+    ov=$1
+    if grep -q -E "^dtoverlay=$ov" $CONFIG; then
+      echo 0
+    else
+      echo 1
+    fi
+}
+
+do_overlay() {
+    ov=$1
+    RET=$2
+    DEFAULT=--defaultno
+    CURRENT=0
+    if [ $(get_overlay $ov) -eq 0 ]; then
+        DEFAULT=
+        CURRENT=1
+    fi
+    if [ $RET -eq $CURRENT ]; then
+        ASK_TO_REBOOT=1
+    fi
+    if [ $RET -eq 0 ]; then
+        sed $CONFIG -i -e "s/^#dtoverlay=$ov/dtoverlay=$ov/"
+        if ! grep -q -E "^dtoverlay=$ov" $CONFIG; then
+            printf "dtoverlay=$ov\n" >> $CONFIG
+        fi
+        STATUS=enabled
+    elif [ $RET -eq 1 ]; then
+        sed $CONFIG -i -e "s/^dtoverlay=$ov/#dtoverlay=$ov/"
+        STATUS=disabled
+    else
+        return $RET
+    fi
+}
+
 
 is_1a=$(i2cdetect -y  1 0x1a 0x1a | grep 1a | awk '{print $2}')
 is_35=$(i2cdetect -y  1 0x35 0x35 | grep 35 | awk '{print $2}')
@@ -37,9 +87,12 @@ is_3b=$(i2cdetect -y  1 0x3b 0x3b | grep 3b | awk '{print $2}')
 rm /etc/asound.conf
 rm /var/lib/alsa/asound.state
 
+RPI_HATS="seeed-2mic-voicecard seeed-4mic-voicecard seeed-8mic-voicecard"
+overlay=""
+
 if [ "x${is_1a}" == "x1a" ] && [ "x${is_35}" == "x" ] ; then
     echo "install 2mic"
-    dtoverlay seeed-2mic-voicecard
+    overlay=seeed-2mic-voicecard
     rm /etc/asound.conf
     rm /var/lib/alsa/asound.state
     echo "create 2mic asound configure file"
@@ -51,7 +104,7 @@ fi
 
 if [ "x${is_3b}" == "x3b" ] && [ "x${is_35}" == "x" ] ; then
     echo "install 4mic"
-    dtoverlay seeed-4mic-voicecard
+    overlay=seeed-4mic-voicecard
     rm /etc/asound.conf
     rm /var/lib/alsa/asound.state
     echo "create 4mic asound configure file"
@@ -63,7 +116,7 @@ fi
 
 if [ "x${is_3b}" == "x3b" ] && [ "x${is_35}" == "x35" ] ; then
     echo "install 6mic"
-    dtoverlay seeed-8mic-voicecard
+    overlay=seeed-8mic-voicecard
     rm /etc/asound.conf
     rm /var/lib/alsa/asound.state
     echo "create 6mic asound configure file"
@@ -73,9 +126,30 @@ if [ "x${is_3b}" == "x3b" ] && [ "x${is_35}" == "x35" ] ; then
     ln -s /etc/voicecard/ac108_6mic.state /var/lib/alsa/asound.state
 fi
 
+if [ "$overlay" ]; then
+
+    echo Install $overlay ...
+    dtoverlay $overlay
+
+    kernel_ver=$(get_kernel_version)
+    # echo kernel_ver=$kernel_ver
+
+    # TODO: dynamic dtoverlay Bug of v4.19.x
+    #       no DT node phandle inserted.
+    if [[ "$kernel_ver" =~ ^4\.19.*$ ]]; then
+        for i in $RPI_HATS; do
+            if [ "$i" == "$overlay" ]; then
+                do_overlay $overlay 0
+            else
+                echo Uninstall $i ...
+                do_overlay $i 1
+            fi
+        done
+    fi
+fi
+
 alsactl restore
 
 #Fore 3.5mm ('headphone') jack
 amixer cset numid=3 1 
 
-
diff --git a/seeed-voicecard.c b/seeed-voicecard.c
index 1a5151d..f08fbd8 100644
--- a/seeed-voicecard.c
+++ b/seeed-voicecard.c
@@ -294,13 +294,19 @@ static int seeed_voice_card_dai_link_of(struct device_node *node,
 	snprintf(prop, sizeof(prop), "%scpu", prefix);
 	cpu = of_get_child_by_name(node, prop);
 
+	if (!cpu) {
+		ret = -EINVAL;
+		dev_err(dev, "%s: Can't find %s DT node\n", __func__, prop);
+		goto dai_link_of_err;
+	}
+
 	snprintf(prop, sizeof(prop), "%splat", prefix);
 	plat = of_get_child_by_name(node, prop);
 
 	snprintf(prop, sizeof(prop), "%scodec", prefix);
 	codec = of_get_child_by_name(node, prop);
 
-	if (!cpu || !codec) {
+	if (!codec) {
 		ret = -EINVAL;
 		dev_err(dev, "%s: Can't find %s DT node\n", __func__, prop);
 		goto dai_link_of_err;
diff --git a/uninstall.sh b/uninstall.sh
index cbade77..0106ed8 100755
--- a/uninstall.sh
+++ b/uninstall.sh
@@ -13,6 +13,42 @@ fi
 
 uname_r=$(uname -r)
 
+CONFIG=/boot/config.txt
+get_overlay() {
+    ov=$1
+    if grep -q -E "^dtoverlay=$ov" $CONFIG; then
+      echo 0
+    else
+      echo 1
+    fi
+}
+
+do_overlay() {
+    ov=$1
+    RET=$2
+    DEFAULT=--defaultno
+    CURRENT=0
+    if [ $(get_overlay $ov) -eq 0 ]; then
+        DEFAULT=
+        CURRENT=1
+    fi
+    if [ $RET -eq $CURRENT ]; then
+        ASK_TO_REBOOT=1
+    fi
+    if [ $RET -eq 0 ]; then
+        sed $CONFIG -i -e "s/^#dtoverlay=$ov/dtoverlay=$ov/"
+        if ! grep -q -E "^dtoverlay=$ov" $CONFIG; then
+            printf "dtoverlay=$ov\n" >> $CONFIG
+        fi
+        STATUS=enabled
+    elif [ $RET -eq 1 ]; then
+        sed $CONFIG -i -e "s/^dtoverlay=$ov/#dtoverlay=$ov/"
+        STATUS=disabled
+    else
+        return $RET
+    fi
+}
+
 
 echo "remove dtbos"
 rm  /boot/overlays/seeed-2mic-voicecard.dtbo || true
@@ -37,6 +73,13 @@ rm  /lib/modules/${uname_r}/kernel/sound/soc/codecs/snd-soc-wm8960.ko || true
 rm  /lib/modules/${uname_r}/kernel/sound/soc/codecs/snd-soc-ac108.ko || true
 rm  /lib/modules/${uname_r}/kernel/sound/soc/bcm/snd-soc-seeed-voicecard.ko || true
 
+echo "remove $CONFIG configuration"
+RPI_HATS="seeed-2mic-voicecard seeed-4mic-voicecard seeed-8mic-voicecard"
+for i in $RPI_HATS; do
+    echo Uninstall $i ...
+    do_overlay $i 1
+done
+
 echo "------------------------------------------------------"
 echo "Please reboot your raspberry pi to apply all settings"
 echo "Thank you!"