HEVC buffering a lot in phones!

Hi, I have an local HEVC movie (720p). In pc there is no buffering while playing this movie, but in my phone, there's a lot of buffering!
(Windows 10 mobile, creators update)
Movie info:

General
Unique ID                      : 42348663308122598639254619844544870105 (0x1FDC0E4DF44EC74CDE088474C138B6D9)
Complete name                  : C:\Users\Ramti\Downloads\Video\Man_with_a_Plan_S02E06_x265_720p.mkv
Format                         : Matroska
Format version                 : Version 4 / Version 2
File size                      : 128 MiB
Duration                       : 20 min 49 s
Overall bit rate               : 858 kb/s
Movie name                     : Man with a Plan S02E06 - RMTeam, RMZ.cr
Description                    : Encoded By RMTeam, http://RMZ.cr
Writing application            : Lavf57.83.100
Writing library                : Lavf57.83.100
ErrorDetectionType             : Per level 1

Video
ID                             : 1
Format                         : HEVC
Format/Info                    : High Efficiency Video Coding
Format profile                 : Main@L3.1@Main
Codec ID                       : V_MPEGH/ISO/HEVC
Duration                       : 20 min 49 s
Width                          : 1 280 pixels
Height                         : 720 pixels
Display aspect ratio           : 16:9
Frame rate mode                : Variable
Original frame rate            : 23.976 FPS
Color space                    : YUV
Chroma subsampling             : 4:2:0
Bit depth                      : 8 bits
Writing library                : x265 2.5+27-0e168bdeb48b:[Linux][GCC 6.4.0][64 bit] 8bit+10bit+12bit
Encoding settings              : cpuid=1173503 / frame-threads=3 / wpp / no-pmode / no-pme / no-psnr / no-ssim / log-level=2 / input-csp=1 / input-res=1280x720 / interlace=0 / total-frames=0 / level-idc=0 / high-tier=1 / uhd-bd=0 / ref=3 / no-allow-non-conformance / no-repeat-headers / annexb / no-aud / no-hrd / info / hash=0 / no-temporal-layers / open-gop / min-keyint=23 / keyint=250 / bframes=4 / b-adapt=2 / b-pyramid / bframe-bias=0 / rc-lookahead=20 / lookahead-slices=4 / scenecut=40 / no-intra-refresh / ctu=64 / min-cu-size=8 / no-rect / no-amp / max-tu-size=32 / tu-inter-depth=1 / tu-intra-depth=1 / limit-tu=0 / rdoq-level=0 / dynamic-rd=0.00 / no-ssim-rd / signhide / no-tskip / nr-intra=0 / nr-inter=0 / no-constrained-intra / strong-intra-smoothing / max-merge=2 / limit-refs=3 / no-limit-modes / me=1 / subme=2 / merange=57 / temporal-mvp / weightp / no-weightb / no-analyze-src-pics / deblock=0:0 / sao / no-sao-non-deblock / rd=3 / no-early-skip / rskip / no-fast-intra / no-tskip-fast / no-cu-lossless / no-b-intra / no-splitrd-skip / rdpenalty=0 / psy-rd=2.00 / psy-rdoq=0.00 / no-rd-refine / analysis-reuse-mode=0 / no-lossless / cbqpoffs=0 / crqpoffs=0 / rc=crf / crf=25.0 / qcomp=0.60 / qpstep=4 / stats-write=0 / stats-read=0 / ipratio=1.40 / pbratio=1.30 / aq-mode=1 / aq-strength=1.00 / cutree / zone-count=0 / no-strict-cbr / qg-size=32 / no-rc-grain / qpmax=69 / qpmin=0 / no-const-vbv / sar=1 / overscan=0 / videoformat=5 / range=0 / colorprim=2 / transfer=2 / colormatrix=2 / chromaloc=0 / display-window=0 / max-cll=0,0 / min-luma=0 / max-luma=255 / log2-max-poc-lsb=8 / vui-timing-info / vui-hrd-info / slices=1 / opt-qp-pps / opt-ref-list-length-pps / no-multi-pass-opt-rps / scenecut-bias=0.05 / no-opt-cu-delta-qp / no-aq-motion / no-hdr / no-hdr-opt / no-dhdr10-opt / analysis-reuse-level=5 / scale-factor=0 / refine-intra=0 / refine-inter=0 / refine-mv=0 / no-limit-sao / ctu-info=0
Language                       : English
Default                        : No
Forced                         : No

Audio
ID                             : 2
Format                         : AAC
Format/Info                    : Advanced Audio Codec
Format profile                 : LC
Codec ID                       : A_AAC-2
Duration                       : 20 min 49 s
Channel(s)                     : 2 channels
Channel positions              : Front: L R
Sampling rate                  : 48.0 kHz
Frame rate                     : 46.875 FPS (1024 SPF)
Compression mode               : Lossy
Writing library                : Lavc57.107.100 aac
Default                        : Yes
Forced                         : No

Here I got the Current state changed of MediaElement, you can see the buffering, time and movie position:

[1/4/2018 10:22:22 PM]	CurrentState: Buffering [Position: 00:00:00]
[1/4/2018 10:22:22 PM]	Buffering: 0.0299999993294477 [Position: 00:00:00]


[1/4/2018 10:22:27 PM]	CurrentState: Buffering [Position: 00:00:00]
[1/4/2018 10:22:27 PM]	Buffering: 0 [Position: 00:00:00]


[1/4/2018 10:22:28 PM]	CurrentState: Buffering [Position: 00:00:00]
[1/4/2018 10:22:28 PM]	Buffering: 0.870000004768372 [Position: 00:00:00]

[1/4/2018 10:22:28 PM]	CurrentState: Playing [Position: 00:00:00]


[1/4/2018 10:22:32 PM]	CurrentState: Buffering [Position: 00:00:04]
[1/4/2018 10:22:32 PM]	Buffering: 0.5 [Position: 00:00:04]

[1/4/2018 10:22:36 PM]	CurrentState: Playing [Position: 00:00:04]


[1/4/2018 10:22:41 PM]	CurrentState: Buffering [Position: 00:00:09]
[1/4/2018 10:22:41 PM]	Buffering: 0.5 [Position: 00:00:09]

[1/4/2018 10:22:46 PM]	CurrentState: Playing [Position: 00:00:09]


[1/4/2018 10:22:52 PM]	CurrentState: Buffering [Position: 00:00:15]
[1/4/2018 10:22:52 PM]	Buffering: 0.5 [Position: 00:00:15]

[1/4/2018 10:22:58 PM]	CurrentState: Playing [Position: 00:00:15]


[1/4/2018 10:22:59 PM]	CurrentState: Buffering [Position: 00:00:16]
[1/4/2018 10:22:59 PM]	Buffering: 0.519999980926514 [Position: 00:00:16]

[1/4/2018 10:23:01 PM]	CurrentState: Playing [Position: 00:00:16]


[1/4/2018 10:23:07 PM]	CurrentState: Buffering [Position: 00:00:22]
[1/4/2018 10:23:07 PM]	Buffering: 0.5 [Position: 00:00:22]

[1/4/2018 10:23:13 PM]	CurrentState: Playing [Position: 00:00:22]

What is the problem of this?

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