Why is my audio saying mono after its muxed?

[killerteengohan]

I encoded my audio from AC3 in Megui to AAC

Mine say AAC 24000Hz Stereo 768kbps [Audio] in Media Player Classic for my audio files before their muxed into MKV.
It doesnt say AAC 48000Hz mono [Audio] untill after ive muxed it in MKVmerge for some reason.

I just tried muxing again right now and before its stereo in Media Player Classic and after it says AAC 48000Hz mono [Audio] in Media Player Classic but the audio doesnt sound any different.

I just tried MKVextract to take the video and audio back out of the MKV file and my original audio file still says AAC24000Hz Stereo 768kbps [Audio] so why its showing as AAC 48000Hz mono [Audio] in Media Player Classic I have no clue.

My settings in the audio encoder on MeGui say Downmix multichannel to Stereo. and keep original sample rate. HE-AAC+PS

It doesnt say anything about mono nor does it on my computer after I check the audio files.

I checked the MKVmerge program and theres no settings for mono or stereo. I even tried muxing someone elses audio and video together and theres says Stereo before and after so it cant be my muxing program.

whats going on here?

[bat999]

whats going on here?

Media Player Classic might be telling lies.
Use MediaInfo

[killerteengohan]

whats going on here?

Media Player Classic might be telling lies.
Use MediaInfo

I did use mediainfo and it doesnt say mono or stereo it says this.

General
Unique ID : 224861304263576674478093161509138145348 (0xA92AB6407D1A1650B7B15A5768E32044)
Complete name : C:\UsersYu-Gi-Oh! GX\Yu-Gi-Oh! GX - 013 - Monkey See, Monkey Duel [DarkDream].mkv
Format : Matroska
Format version : Version 2
File size : 250 MiB
Duration : 20mn 28s
Overall bit rate : 1 709 Kbps
Encoded date : UTC 2011-10-02 16:40:10
Writing application : mkvmerge v4.9.1 ('Ich will') built on Jul 11 2011 23:53:15
Writing library : libebml v1.2.1 + libmatroska v1.1.1

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L3.0
Format settings, CABAC : Yes
Format settings, ReFrames : 5 frames
Format settings, GOP : M=1, N=2
Codec ID : V_MPEG4/ISO/AVC
Duration : 20mn 28s
Nominal bit rate : 1 638 Kbps
Width : 640 pixels
Height : 480 pixels
Display aspect ratio : 4:3
Frame rate : 23.976 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.222
Title :
Writing library : x264 core 116 r2074 2641b9e
Encoding settings : cabac=1 / ref=5 / deblock=1:1:1 / analyse=0x3:0x133 / me=umh / subme=7 / psy=1 / psy_rd=0.40:0.00 / 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=3 / sliced_threads=0 / nr=0 / decimate=0 / 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=250 / keyint_min=23 / scenecut=40 / intra_refresh=0 / rc_lookahead=50 / rc=2pass / mbtree=1 / bitrate=1638 / ratetol=1.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / ip_ratio=1.40 / aq=1:1.00

Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : HE-AACv2 / HE-AAC / LC
Codec ID : A_AAC
Duration : 20mn 28s
Channel(s) : 2 channels / 1 channel / 1 channel
Channel positions : Front: L R / Front: C / Front: C
Sampling rate : 48.0 KHz / 48.0 KHz / 24.0 KHz
Compression mode : Lossy
Title : English
Language : English

[bat999]

Format : AAC
Format/Info : Advanced Audio Codec
Format profile : HE-AACv2 / HE-AAC / LC
Codec ID : A_AAC
Duration : 20mn 28s
Channel(s) : 2 channels / 1 channel / 1 channel
Channel positions : Front: L R / Front: C / Front: C
Sampling rate : 48.0 KHz / 48.0 KHz / 24.0 KHz

It looks like you have used "HE-AACv2 / HE-AAC / LC".
What other audio options are available with MeGui?

[killerteengohan]

Format : AAC
Format/Info : Advanced Audio Codec
Format profile : HE-AACv2 / HE-AAC / LC
Codec ID : A_AAC
Duration : 20mn 28s
Channel(s) : 2 channels / 1 channel / 1 channel
Channel positions : Front: L R / Front: C / Front: C
Sampling rate : 48.0 KHz / 48.0 KHz / 24.0 KHz

It looks like you have used "HE-AACv2 / HE-AAC / LC".
What other audio options are available with MeGui?

All I see are 3 options

AAC-LC

HE-AAC

HE-AAC+PS

Im using the +PS one

the other HE-AAC is almost double the file size and AAC-LC is double if not more than the file size I get from HE-AAC+PS but those 2 show up as stereo at least in MPC

[bat999]

Im using the +PS one

the other HE-AAC is almost double the file size and AAC-LC is double if not more than the file size I get from HE-AAC+PS but those 2 show up as stereo at least in MPC

OK
If you want a small file size stay with this +PS audio option.
It is stereo but "HE-AAC+PS" is confusing the MediaInfo program.

This is difficult for MediaInfo to understand:-

Channel(s) : 2 channels / 1 channel / 1 channel
Channel positions : Front: L R / Front: C / Front: C
Sampling rate : 48.0 KHz / 48.0 KHz / 24.0 KHz

[killerteengohan]

Im using the +PS one

the other HE-AAC is almost double the file size and AAC-LC is double if not more than the file size I get from HE-AAC+PS but those 2 show up as stereo at least in MPC

OK
If you want a small file size stay with this +PS audio option.
It is stereo but "HE-AAC+PS" is confusing the MediaInfo program.

This is difficult for MediaInfo to understand:-

Channel(s) : 2 channels / 1 channel / 1 channel
Channel positions : Front: L R / Front: C / Front: C
Sampling rate : 48.0 KHz / 48.0 KHz / 24.0 KHz

But thats only after its muxed that media player classic says that its mono. before its muxed it says the audio is AAC 24000Hz Stereo 768kbps [Audio]

Why does it change to mono just because its in an MKV file now?

shows up in mediainfo like this before being muxed

General
Complete name : C:\Users\VTS_04_1 T81 2_0ch 224Kbps DELAY 0ms.mp4
Format : MPEG-4
Format profile : Base Media / Version 2
Codec ID : mp42
File size : 10.1 MiB
Duration : 19mn 57s
Overall bit rate : 70.4 Kbps
Encoded date : UTC 2012-02-06 19:36:49
Tagged date : UTC 2012-02-06 19:37:23

Audio
ID : 1
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : HE-AACv2 / HE-AAC / LC
Codec ID : 40
Duration : 19mn 57s
Bit rate mode : Variable
Bit rate : 69.6 Kbps
Maximum bit rate : 79.0 Kbps
Channel(s) : 2 channels / 1 channel / 1 channel
Channel positions : Front: L R / Front: C / Front: C
Sampling rate : 48.0 KHz / 48.0 KHz / 24.0 KHz
Compression mode : Lossy
Stream size : 9.94 MiB (99%)
Writing library : Nero AAC codec 1.5.4.0
Encoding settings : -br 192000 -hev2
Encoded date : UTC 2012-02-06 19:36:49
Tagged date : UTC 2012-02-06 19:37:23
Material_Duration : 1197525
Material_StreamSize : 10420089