I also have this issue, no dd 5.1 sound over optical, DTS is fine.
Im on latest firmware, and it is affecting all my files with dd 5.1
Power cycle and factory reset does not help
Please say if you need more info
EDIT: Just tried 1.04.12 firmware - it plays dd 5.1 fine with this firmware…
Here is mediainfo on one of the files
General Unique ID : 250170795586935734265168268252394044272 (0xBC35248443DFC5F59125D06CEF303B70) Complete name : Z:\Iron Man 2.mkv Format : Matroska Format version
: Version 2
File size : 6.41 GiB Duration : 2h 4mn
Overall bit rate
: 7 366 Kbps Encoded date : UTC 2010-09-12 06:29:50 Writing application
: mkvmerge v4.0.0 (‘The Stars were mine’) built on Jun 6 2010 16:18:42 Writing library
: libebml v1.0.0 + libmatroska v1.0.0
Video ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.1
Format settings, CABAC : Yes
Format settings, ReFrames : 11
frames Codec ID : V_MPEG4/ISO/AVC
Duration : 2h 4mn
Bit rate : 6 500 Kbps
Width : 1 280 pixels
Height : 544 pixels
Display aspect ratio : 2.35:1
Frame rate : 23.976 fps
Color space : YUV Chroma
subsampling : 4:2:0 Bit depth : 8 bits
Scan type : Progressive Bits/(Pixel*Frame) : 0.389
Stream size : 5.53 GiB (86%)
Title : Iron Man 2 (2010)
Writing library : x264 core 104 r1713 c276662
Encoding settings : cabac=1 / ref=11 / deblock=1:-3:-3 / analyse=0x3:0x113 / me=tesa / subme=10 / psy=1 / psy_rd=1.05:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=2 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=0 / chroma_qp_offset=-2 / threads=12 / sliced_threads=0 / nr=0 / decimate=0 / interlaced=0 / constrained_intra=0 / bframes=8 / b_pyramid=2 / b_adapt=2 / b_bias=0 / direct=3 / weightb=1 / open_gop=0 / weightp=2 / keyint=250 / keyint_min=23 / scenecut=40 / intra_refresh=0 / rc=2pass / mbtree=0 / bitrate=6500 / ratetol=1.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / ip_ratio=1.40 / pb_ratio=1.30 / aq=1:0.90
Language : English
Default : No
Forced : No
Audio #1 ID : 2
Format : AC-3
Format/Info : Audio Coding 3
Mode extension : CM (complete main)
Codec ID : A_AC3
Duration : 2h 4mn
Bit rate mode : Constant Bit rate : 640 Kbps
Channel(s) : 6 channels
Channel positions : Front: L C R, Side: L R, LFE
Sampling rate : 48.0 KHz
Bit depth : 16 bits
Compression mode : Lossy Stream
size : 571 MiB (9%)
Title : AC3 5.1 @ 640 kbps
Language : English
Default : No
Forced : No
