Issue: FLAC audio not playing
Solution: Disabling AC3 in Plex settings
I have a movie in which the audio does not work while playing it through Plex on my PS4. The MKV itself has audio in the FLAC format but it doesn’t work while playing through Plex.
At first, I assumed the audio format was not supported by Plex but I then went head and played it using Plex on my Xbox One and the audio played without issues. So this goes to show that the issue is with the Plex PS4 app.
Looking at the PlayStation website, I can see FLAC is not a supported audio format (at least not for videos). Now I would have just assumed this was the cause but Plex should transcode the audio to a format that the PS4 can handle. Why it’s not doing so was the issue at hand.
Playing around with the settings, I have found that disabling AC3 in Plex fixes the issue. I’m not sure why that fixes it but it does.
Here’s the metadata I pulled using MediaInfo in case you need it.
General
Unique ID : 182868284484421787873121086008998324244 (0x89932686F4195754A25B9A1E08816814)
Complete name : C:\Users\*****\Desktop\Media\Movies\Seven Samurai (1954)\Seven Samurai (1954).mkv
Format : Matroska
Format version : Version 4 / Version 2
File size : 18.6 GiB
Duration : 3 h 27 min
Overall bit rate mode : Variable
Overall bit rate : 12.9 Mb/s
Encoded date : UTC 2015-11-12 15:17:00
Writing application : mkvmerge v8.5.1 ('Where you lead I will follow') 64bit
Writing library : libebml v1.3.3 + libmatroska v1.4.4
Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.1
Format settings, CABAC : Yes
Format settings, ReFrames : 5 frames
Codec ID : V_MPEG4/ISO/AVC
Duration : 3 h 27 min
Bit rate : 12.3 Mb/s
Width : 1 440 pixels
Height : 1 080 pixels
Display aspect ratio : 4:3
Frame rate mode : Constant
Frame rate : 23.976 (24000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.329
Stream size : 17.7 GiB (95%)
Writing library : x264 core 148 r2638 7599210
Encoding settings : cabac=1 / ref=5 / deblock=1:0:0 / analyse=0x3:0x113 / me=umh / subme=8 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=12 / lookahead_threads=2 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=2 / b_bias=0 / direct=3 / weightb=1 / open_gop=0 / weightp=2 / keyint=240 / keyint_min=24 / scenecut=40 / intra_refresh=0 / rc_lookahead=50 / rc=2pass / mbtree=1 / bitrate=12269 / ratetol=1.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / vbv_maxrate=62500 / vbv_bufsize=78125 / nal_hrd=none / filler=0 / ip_ratio=1.40 / aq=1:1.00
Default : Yes
Forced : No
Color range : Limited
Matrix coefficients : BT.709
Audio
ID : 2
Format : FLAC
Format/Info : Free Lossless Audio Codec
Codec ID : A_FLAC
Duration : 3 h 27 min
Bit rate mode : Variable
Bit rate : 583 kb/s
Channel(s) : 1 channel
Channel positions : Front: C
Sampling rate : 48.0 kHz
Frame rate : 11.719 FPS (4096 spf)
Bit depth : 24 bits
Stream size : 863 MiB (5%)
Writing library : libFLAC 1.2.1 (UTC 2007-09-17)
Language : Japanese
Default : Yes
Forced : No
Text
ID : 3
Format : UTF-8
Codec ID : S_TEXT/UTF8
Codec ID/Info : UTF-8 Plain Text
Duration : 3 h 26 min
Bit rate : 25 b/s
Count of elements : 1336
Stream size : 38.8 KiB (0%)
Language : English
Default : Yes
Forced : No
Menu
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