diff --git a/layers/meta-balena-allwinner/recipes-bsp/nanopi-air-bt/nanopi-air-bt/99-nanopi-air-bt.rules b/layers/meta-balena-allwinner/recipes-bsp/nanopi-air-bt/nanopi-air-bt/99-nanopi-air-bt.rules
index 61d7e6b..5df2599 100644
--- a/layers/meta-balena-allwinner/recipes-bsp/nanopi-air-bt/nanopi-air-bt/99-nanopi-air-bt.rules
+++ b/layers/meta-balena-allwinner/recipes-bsp/nanopi-air-bt/nanopi-air-bt/99-nanopi-air-bt.rules
@@ -1 +1 @@
-ACTION=="add", SUBSYSTEM=="tty", ATTR{iomem_base}=="0x1C28C00", TAG+="systemd", ENV{SYSTEMD_WANTS}="nanopi-air-bt@'%E{DEVNAME}'.service"
+ACTION=="add", SUBSYSTEM=="tty", ATTR{iomem_base}=="0x1C28C00", TAG+="systemd", ENV{SYSTEMD_WANTS}="nanopi-air-bt@%k.service"
diff --git a/layers/meta-balena-allwinner/recipes-bsp/nanopi-air-bt/nanopi-air-bt/nanopi-air-bt-start b/layers/meta-balena-allwinner/recipes-bsp/nanopi-air-bt/nanopi-air-bt/nanopi-air-bt-start
index 8abf14b..1855a07 100755
--- a/layers/meta-balena-allwinner/recipes-bsp/nanopi-air-bt/nanopi-air-bt/nanopi-air-bt-start
+++ b/layers/meta-balena-allwinner/recipes-bsp/nanopi-air-bt/nanopi-air-bt/nanopi-air-bt-start
@@ -16,7 +16,7 @@ echo 1 > /sys/class/gpio/gpio205/value
 CHIP_REV=`dmesg | grep brcmfm | grep "chip 0x00a9a6" | awk '{print $11}'`
 BT_FIRMWARE="bcm43438a0.hcd" # AP6212 chip
 
-if [ "$CHIP_REV" = "0x000001" ]; then
+if dmesg | grep -q "chip BCM43430/1"; then
     BT_FIRMWARE="bcm43438a1.hcd" # AP6212A chip
 fi
 
diff --git a/layers/meta-balena-allwinner/recipes-bsp/nanopi-air-bt/nanopi-air-bt/nanopi-air-bt@.service b/layers/meta-balena-allwinner/recipes-bsp/nanopi-air-bt/nanopi-air-bt/nanopi-air-bt@.service
index 40f7b29..65f9ae8 100644
--- a/layers/meta-balena-allwinner/recipes-bsp/nanopi-air-bt/nanopi-air-bt/nanopi-air-bt@.service
+++ b/layers/meta-balena-allwinner/recipes-bsp/nanopi-air-bt/nanopi-air-bt/nanopi-air-bt@.service
@@ -3,7 +3,7 @@ Description=Ampak AP6212A Bluetooth HCI on Nanopi Neo Air
 
 [Service]
 Type=simple
-ExecStart=/bin/bash /usr/bin/nanopi-air-bt-start %I
+ExecStart=/bin/bash /usr/bin/nanopi-air-bt-start /dev/%I
 
 [Install]
 WantedBy=multi-user.target