main/bluez: 32-bit bug with musl 1.2 - Bluetooth AVRCP key events not reaching input system

I'm transitioning a working PiZeroW 3.11 setup to 3.13: Pi sends audio to BT headsets, and gets AVRCP commands (play/pause/etc) from headset keys through busybox acpi.

On 3.13 bluetooth AVRCP events do no seem so come-up anymore from connected headset at key press. Audio is ok (bluez-alsa).

Testing with evtest does not give much clue, except no key press is detected... Tested with several headsets which work fine on 3.11, and also ok on Ubuntu 18.04 Any hint?

tiny-radiocd:~$ sudo bluetoothctl
Agent registered
[Vivan  BT600]# info
Device XX:XX:XX:XX:XX:XX (public)
	Name: Vivan  BT600
	Alias: Vivan  BT600
	Class: 0x00240404
	Icon: audio-card
	Paired: yes
	Trusted: yes
	Blocked: no
	Connected: yes
	LegacyPairing: no
	UUID: Audio Sink                (0000110b-0000-1000-8000-00805f9b34fb)
	UUID: A/V Remote Control Target (0000110c-0000-1000-8000-00805f9b34fb)
	UUID: A/V Remote Control        (0000110e-0000-1000-8000-00805f9b34fb)
	UUID: Handsfree                 (0000111e-0000-1000-8000-00805f9b34fb)
[Vivan  BT600]# 

tiny-radiocd:~$ sudo evtest
No device specified, trying to scan all of /dev/input/event*
Available devices:
/dev/input/event0:	Mitsumi Electric Apple USB Keyboard
/dev/input/event1:	Logitech M4848
/dev/input/event2:	MacALLY USB Two Button Mini Mouse
/dev/input/event3:	Vivan  BT600 (AVRCP)
Select the device event number [0-3]: 3
Input driver version is 1.0.1
Input device ID: bus 0x5 vendor 0x0 product 0x0 version 0x0
Input device name: "Vivan  BT600 (AVRCP)"
Supported events:
  Event type 0 (EV_SYN)
  Event type 1 (EV_KEY)
    Event code 2 (KEY_1)
    Event code 3 (KEY_2)
    Event code 4 (KEY_3)
    Event code 5 (KEY_4)
    Event code 6 (KEY_5)
    Event code 7 (KEY_6)
    Event code 8 (KEY_7)
    Event code 9 (KEY_8)
    Event code 10 (KEY_9)
    Event code 11 (KEY_0)
    Event code 28 (KEY_ENTER)
    Event code 52 (KEY_DOT)
    Event code 59 (KEY_F1)
    Event code 60 (KEY_F2)
    Event code 61 (KEY_F3)
    Event code 62 (KEY_F4)
    Event code 63 (KEY_F5)
    Event code 64 (KEY_F6)
    Event code 65 (KEY_F7)
    Event code 66 (KEY_F8)
    Event code 67 (KEY_F9)
    Event code 103 (KEY_UP)
    Event code 105 (KEY_LEFT)
    Event code 106 (KEY_RIGHT)
    Event code 108 (KEY_DOWN)
    Event code 113 (KEY_MUTE)
    Event code 114 (KEY_VOLUMEDOWN)
    Event code 115 (KEY_VOLUMEUP)
    Event code 138 (KEY_HELP)
    Event code 139 (KEY_MENU)
    Event code 163 (KEY_NEXTSONG)
    Event code 165 (KEY_PREVIOUSSONG)
    Event code 166 (KEY_STOPCD)
    Event code 167 (KEY_RECORD)
    Event code 168 (KEY_REWIND)
    Event code 171 (KEY_CONFIG)
    Event code 174 (KEY_EXIT)
    Event code 200 (KEY_PLAYCD)
    Event code 201 (KEY_PAUSECD)
    Event code 208 (KEY_FASTFORWARD)
    Event code 353 (KEY_SELECT)
    Event code 356 (KEY_POWER2)
    Event code 358 (KEY_INFO)
    Event code 362 (KEY_PROGRAM)
    Event code 364 (KEY_FAVORITES)
    Event code 395 (KEY_LIST)
    Event code 398 (KEY_RED)
    Event code 399 (KEY_GREEN)
    Event code 400 (KEY_YELLOW)
    Event code 401 (KEY_BLUE)
    Event code 402 (KEY_CHANNELUP)
    Event code 403 (KEY_CHANNELDOWN)
    Event code 405 (KEY_LAST)
  Event type 2 (EV_REL)
Key repeat handling:
  Repeat type 20 (EV_REP)
    Repeat code 0 (REP_DELAY)
      Value    250
    Repeat code 1 (REP_PERIOD)
      Value     33
Properties:
Testing ... (interrupt to exit)