Orange Pi Zero+ IR Receiver

Hi, I have trouble getting an IR receiver on the Orange Pi Zero+ to work.

IR-Hardware: Orange Pi Zero Interface Board v 1.2 https://www.aliexpress.com/store/product/New-Orange-Pi-Zreo-Expansion-board-Interface-board-Development-board-beyond-Raspberry-Pi/1553371_32770665186.html

I use Armbian 5.65 (Debian stretch), Kernel 4.14.78

I activate the IR receiver by adding "cir" to overlays in /boot/armbianEnv.txt

On boot it is activated and the sunxi_cir module is loaded (and also lirc_dev, don't know why), see dmesg output:

[    5.245866] lirc_dev: IR Remote Control driver registered, major 244
[    5.255140] IR LIRC bridge handler initialized
[    5.257318] Registered IR keymap rc-empty
[    5.257510] rc rc0: sunxi-ir as /devices/platform/soc/1f02000.ir/rc/rc0
[    5.257779] input: sunxi-ir as /devices/platform/soc/1f02000.ir/rc/rc0/input0
[    5.260011] rc rc0: lirc_dev: driver ir-lirc-codec (sunxi-ir) registered at minor = 0
[    5.260178] sunxi-ir 1f02000.ir: initialized sunXi IR driver

But when I check the input with evtest, nothing shows up:

No device specified, trying to scan all of /dev/input/event*
Available devices:
/dev/input/event0:      sunxi-ir
Select the device event number [0-0]: 0
Input driver version is 1.0.1
Input device ID: bus 0x19 vendor 0x1 product 0x1 version 0x100
Input device name: "sunxi-ir"
Supported events:
  Event type 0 (EV_SYN)
  Event type 1 (EV_KEY)
    Event code 152 (KEY_SCREENLOCK)
  Event type 4 (EV_MSC)
    Event code 4 (MSC_SCAN)
Key repeat handling:
  Repeat type 20 (EV_REP)
    Repeat code 0 (REP_DELAY)
      Value    500
    Repeat code 1 (REP_PERIOD)
      Value    125
Properties:
Testing ... (interrupt to exit)

Any hints on how to progress?

Thanks!

Edit:

After trying several remotes it seems the signal is received but not handled the way I expected. Looking at dmesg again after some time, there are lots of "IR event FIFO is full!"-Errors:

...
[ 2596.485136] rc rc0: IR event FIFO is full!
[ 2596.485141] rc rc0: IR event FIFO is full!
[ 2596.485146] rc rc0: IR event FIFO is full!
[ 2596.485151] rc rc0: IR event FIFO is full!
...

I also tried unloading ir_lirc_codec and lirc_dev modules (modprobe -r) but behavior is still the same.