Mi Box 3 build properties

build.prop

# begin build properties
# autogenerated by buildinfo.sh
ro.build.id=MHC19J
ro.build.display.id=once-user 6.0.1 MHC19J 540
ro.build.version.incremental=540
ro.build.version.sdk=23
ro.build.version.preview_sdk=0
ro.build.version.codename=REL
ro.build.version.all_codenames=REL
ro.build.version.release=6.0.1
ro.build.version.security_patch=2016-06-01
ro.build.version.base_os=
ro.build.date=Sat Sep 24 16:52:06 CST 2016
ro.build.date.utc=1474707126
ro.build.type=user
ro.build.user=jenkins
ro.build.host=qh-dk-box-bsp01
ro.build.tags=release-keys
ro.build.flavor=once-user
ro.product.model=MIBOX3
ro.product.brand=Xiaomi
ro.product.name=once
ro.product.device=once
ro.product.board=once
# ro.product.cpu.abi and ro.product.cpu.abi2 are obsolete,
# use ro.product.cpu.abilist instead.
ro.product.cpu.abi=armeabi-v7a
ro.product.cpu.abi2=armeabi
ro.product.cpu.abilist=armeabi-v7a,armeabi
ro.product.cpu.abilist32=armeabi-v7a,armeabi
ro.product.cpu.abilist64=
ro.product.manufacturer=Xiaomi
ro.product.locale=en-US
ro.wifi.channels=14
ro.board.platform=gxl
# ro.build.product is obsolete; use ro.product.device
ro.build.product=once
# Do not try to parse description, fingerprint, or thumbprint
ro.build.description=once-user 6.0.1 MHC19J 540 release-keys
ro.build.fingerprint=Xiaomi/once/once:6.0.1/MHC19J/540:user/release-keys
ro.build.characteristics=tv,nosdcard
# end build properties
#
# from device/xiaomi/once/system.prop
#
# Set display related config
ro.platform.has.mbxuimode=true
ro.platform.has.realoutputmode=true
ro.platform.keepbackground.app=com.droidlogic.PPPoE
#camera max to 720p
ro.camera.preview.MaxSize=1280x720
ro.camera.preview.LimitedRate=1280x720x30,640x480x30,320x240x28
ro.camera.preview.UseMJPEG=1
#if wifi Only
ro.radio.noril=true

ro.sf.lcd_density=320

#the prop is used for enable or disable
#DD+/DD force output when HDMI EDID is not supported
#by default,the force output mode is enabled.
#Note,please do not set the prop to true by default
#only for netflix,just disable the feature.so set the prop to true
ro.platform.disable.audiorawout=false

#Dolby DD+ decoder option
#this prop to for videoplayer display the DD+/DD icon when playback
ro.platform.support.dolby=true
#DTS decoder option
#display dts icon when playback
ro.platform.support.dts=true
#DTS-HD support prop
#ro.platform.support.dtstrans=true
#ro.platform.support.dtsmulasset=true
#DTS-HD prop end
# Enable player buildin
media.amplayer.seekkeyframe=true
media.amsuperplayer.enable=true
media.amplayer.enable-acodecs=ac3,eac3,rm,dts
media.amplayer.enable=true
media.amsuperplayer.m4aplayer=STAGEFRIGHT_PLAYER
media.amsuperplayer.defplayer=PV_PLAYER
media.amplayer.thumbnail=true
media.amplayer.widevineenable=true
media.amplayer.dsource4local=1
media.amplayer.dropwaitxms=100

media.arm.audio.decoder=ape,flac,dts,ac3,eac3,mp3,aac,vorbis,raac,cook,amr,pcm,adpcm,aac_latm,rm
media.wfd.use-pcm-audio=false
media.wfd.videoresolution-type=1
media.wfd.videoresolution-group=0
media.wfd.videoframerate=24
media.wfd.video-bitrate=2000000
media.html5videowin.enable=1
media.decoder.vfm.defmap=decoder ppmgr deinterlace amvideo
media.decoder.vfm.drmmap=decoder amvideo

#add for video boot, 1 means use video boot, others not .
service.bootvideo=0

# Define drm for this device
drm.service.enabled=1

#used forward seek for libplayer
media.libplayer.seek.fwdsearch=1

#fix hls sync
libplayer.livets.softdemux=1
libplayer.netts.recalcpts=1

#map volume
ro.audio.mapvalue=0,0,0,0

#By default, primary storage is physical
#ro.vold.primary_physical=true

#Support storage visible to apps
persist.fw.force_adoptable=true

#add livhls,libcurl as default hls
media.libplayer.curlenable=true
media.libplayer.modules=vhls_mod,dash_mod,curl_mod,prhls_mod,vm_mod


#Hdmi In
ro.sys.hdmiin.enable=false
mbx.hdmiin.switchfull=false
mbx.hdmiin.videolayer=false

#
dalvik.vm.heapstartsize=16m
dalvik.vm.heapgrowthlimit=256m
dalvik.vm.heapsize=512m
dalvik.vm.heaptargetutilization=0.75
dalvik.vm.heapminfree=512k
dalvik.vm.heapmaxfree=8m

# usb mode
ro.usbtodevice=0xc8834434 0xDFFFFFFF
ro.usbtohost=0xc8834434 0xDDFFFFFF

#
# ADDITIONAL_BUILD_PROPERTIES
#
ro.config.wallpaper=/system/etc/default_wallpaper.png
persist.sys.media.avsync=true
sys.fb.bits=32
ro.hdmi.device_type=4
persist.sys.hdmi.keep_awake=false
ro.carrier=wifi-only
wifi.interface=wlan0
config.disable_bluetooth=false
ro.adb.secure=1
sys.display-size=3840x2160
ro.opengles.version=131072
debug.hwui.render_dirty_regions=false
camera.disable_zsl_mode=1
ro.app.optimization=false
ro.com.google.clientidbase=android-xiaomi-tv
ro.setupwizard.mode=OPTIONAL
ro.com.google.gmsversion=6.0_r2
ro.nrdp.modelgroup=XIAOMIM12TRIAL
drm.service.enable=true
persist.sys.dalvik.vm.lib.2=libart
dalvik.vm.isa.arm.variant=cortex-a9
dalvik.vm.isa.arm.features=default
net.bt.name=Android
dalvik.vm.stack-trace-file=/data/anr/traces.txt
ro.expect.recovery_id=XXX

Do you have build.prop from Android 9 (Pie) TV of this MIBOX?