PowerDVD 21 and HD Audio in .mkv?

[meimeiriver]

I get an 'Unsupported audio format' when playing HD Audio (LPCM) inside an .mkv file. Works fine with .mt2s files. What gives? Just bought PowerDVD 21 Ultra today.

[ProWo]

LPCM 16/24/32/64 bit?
Post a mediainfo report of you mkv file here (text format).

[meimeiriver]

LPCM 16/24/32/64 bit?
Post a mediainfo report of you mkv file here (text format).

Here is an example, in full (see below). Just a standard 5.1 LPCM audio track. Plays with everything, even with PowweDVD 21, but not inside an .mkv container with an UHD stream.

General
Unique ID                                : 187114675336600084842924770818267196199 (0x8CC4F9C2A89DC20D4B1B0AA70CDEAB27)
Complete name                            : N:\Confessions Of a Shopaholic REGRADED (UHD).mkv
Format                                   : Matroska
Format version                           : Version 4
File size                                : 51.5 GiB
Duration                                 : 1 h 44 min
Overall bit rate                         : 70.7 Mb/s
Encoded date                             : UTC 2022-02-10 17:22:57
Writing application                      : mkvmerge v65.0.0 ('Too Much') 64-bit
Writing library                          : libebml v1.4.2 + libmatroska v1.6.4

Video
ID                                       : 1
Format                                   : HEVC
Format/Info                              : High Efficiency Video Coding
Format profile                           : Main 10@L5@Main
Codec ID                                 : V_MPEGH/ISO/HEVC
Duration                                 : 1 h 44 min
Bit rate                                 : 63.8 Mb/s
Width                                    : 3 840 pixels
Height                                   : 2 160 pixels
Display aspect ratio                     : 16:9
Frame rate mode                          : Constant
Frame rate                               : 23.976 (24000/1001) FPS
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 10 bits
Bits/(Pixel*Frame)                       : 0.321
Stream size                              : 46.5 GiB (90%)
Writing library                          : x265 3.5+2-g2b25c9ba0+45:[Windows][GCC 10.2.0][64 bit] Yuuki 10bit
Encoding settings                        : rc=crf / crf=10.0000 / qcomp=0.60 / qpstep=4 / stats-write=0 / stats-read=0 / no-lossless / no-cu-lossless / aq-mode=2 / aq-strength=1.00 / cbqpoffs=0 / crqpoffs=0 / ipratio=1.40 / pbratio=1.30 / psy-rd=2.00 / psy-rdoq=0.00 / deblock=0:0 / ref=3 / limit-refs=1 / no-limit-modes / bframes=4 / b-adapt=2 / bframe-bias=0 / b-pyramid / b-intra / weightp / no-weightb / min-keyint=23 / max-keyint=250 / rc-lookahead=20 / gop-lookahead=0 / scenecut=40 / hist-scenecut=0 / radl=0 / max-cu-size=64 / min-cu-size=8 / me=1 / subme=2 / merange=57 / rdoq-level=0 / rd=3 / rdpenalty=0 / dynamic-rd=0.00 / no-rd-refine / ----- / cutree / sao / no-rect / no-amp / open-gop / wpp / no-pmode / no-pme / no-psnr / no-ssim / nr-intra=0 / nr-inter=0 / no-constrained-intra / strong-intra-smoothing / max-tu-size=32 / tu-inter-depth=1 / tu-intra-depth=1 / limit-tu=0 / qg-size=32 / qpmax=69 / qpmin=0 / ----- / cpuid=1111039 / frame-threads=4 / numa-pools=24 / log-level=2 / input-csp=1 / input-res=3840x2160 / interlace=0 / level-idc=0 / high-tier=1 / uhd-bd=0 / no-allow-non-conformance / no-repeat-headers / no-aud / no-hrd / info / hash=0 / no-temporal-layers / lookahead-slices=8 / no-splice / no-intra-refresh / no-ssim-rd / signhide / no-tskip / max-merge=3 / temporal-mvp / no-frame-dup / no-hme / no-analyze-src-pics / no-sao-non-deblock / selective-sao=4 / early-skip / rskip / no-fast-intra / no-tskip-fast / no-splitrd-skip / zone-count=0 / no-strict-cbr / no-rc-grain / no-const-vbv / sar=0 / overscan=0 / videoformat=5 / range=0 / colorprim=1 / transfer=2 / colormatrix=1 / chromaloc=0 / display-window=0 / cll=0,0 / min-luma=0 / max-luma=1023 / log2-max-poc-lsb=8 / vui-timing-info / vui-hrd-info / slices=1 / no-opt-qp-pps / no-opt-ref-list-length-pps / no-multi-pass-opt-rps / scenecut-bias=0.05 / hist-threshold=0.03 / no-opt-cu-delta-qp / no-aq-motion / no-hdr10 / no-hdr10-opt / no-dhdr10-opt / no-idr-recovery-sei / analysis-reuse-level=0 / analysis-save-reuse-level=0 / analysis-load-reuse-level=0 / scale-factor=0 / refine-intra=0 / refine-inter=0 / refine-mv=1 / refine-ctu-distortion=0 / no-limit-sao / ctu-info=0 / no-lowpass-dct / refine-analysis-type=0 / copy-pic=1 / max-ausize-factor=1.0 / no-dynamic-refine / no-single-sei / no-hevc-aq / no-svt / no-field / qp-adaptation-range=1.00 / scenecut-aware-qp=0conformance-window-offsets / right=0 / bottom=0 / decoder-max-rate=0 / no-vbv-live-multi-pass
Language                                 : English
Default                                  : Yes
Forced                                   : No
Color range                              : Limited
Color primaries                          : BT.709
Matrix coefficients                      : BT.709

Audio
ID                                       : 2
Format                                   : PCM
Format settings                          : Little / Signed
Codec ID                                 : A_PCM/INT/LIT
Duration                                 : 1 h 44 min
Bit rate mode                            : Constant
Bit rate                                 : 6 912 kb/s
Channel(s)                               : 6 channels
Sampling rate                            : 48.0 kHz
Frame rate                               : 25.000 FPS (1920 SPF)
Bit depth                                : 24 bits
Stream size                              : 5.03 GiB (10%)
Language                                 : English
Default                                  : Yes
Forced                                   : No

[ProWo]

Could be the Bit depth (24 bits in your case).
You should check if another working PCM is 24 bits too.
mkv or m2ts are only containers, but the player fails a codec.