DTS to ac3

[Han Solo1]

I am trying to convert DTS to 6 Chanel ac3 audio in order to play an mkv file on a LG42LH50 LCD TV which is unable to play DTS audio. The mkv file has the following info:

General
Complete name : J:\Libraries\Videos\
Format : Matroska
File size : 6.28 GiB
Duration : 2h 9mn
Overall bit rate : 6 923 Kbps
Movie name :
Encoded date : UTC 2009-08-11 03:54:03
Writing application : mkvmerge v2.9.7 ('Tenderness') built on Jul 1 2009 18:43:35
Writing library : libebml v0.7.7 + libmatroska v0.8.1

Video
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.1
Format settings, CABAC : Yes
Format settings, ReFrames : 4 frames
Muxing mode : Container profile=Unknown@4.1
Codec ID : V_MPEG4/ISO/AVC
Duration : 2h 9mn
Bit rate : 5 103 Kbps
Nominal bit rate : 5 412 Kbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16/9
Frame rate : 24.000 fps
Resolution : 24 bits
Colorimetry : 4:2:0
Scan type : Progressive
Bits/(Pixel*Frame) : 0.109
Title :
Writing library : x264 core 68 r1195M 5d75a9b
Encoding settings : cabac=1 / ref=4 / deblock=1:1:1 / analyse=0x3:0x133 / me=umh / subme=7 / psy_rd=1.0:0.0 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=2 / 8x8dct=1 / cqm=0 / deadzone=21,11 / chroma_qp_offset=-2 / threads=3 / nr=0 / decimate=1 / mbaff=0 / bframes=3 / b_pyramid=0 / b_adapt=1 / b_bias=0 / direct=3 / wpredb=1 / keyint=240 / keyint_min=24 / scenecut=40 / rc=2pass / bitrate=5412 / ratetol=1.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / vbv_maxrate=25000 / vbv_bufsize=25000 / ip_ratio=1.40 / pb_ratio=1.30 / aq=1:1.00
Language : English

Audio
Format : DTS
Format/Info : Digital Theater Systems
Codec ID : A_DTS
Duration : 2h 9mn
Bit rate mode : Constant
Bit rate : 1 536 Kbps

What would be the best way to do this?
I used mkv2vob to transcode the DTS to ac3 successfully, then I used mkvcleaver to extract the h.264 and sub files. I then used mkvmerge to create a new mkv file but I think mkvmerge still has to add the DTS audio the result is out of sync audio.
Recently I used mkvcleaver to extract video and sub again but this time I used video options in order to conver h.264 to avi files.
I then used mkvmerge to mux the ac3 and 3 avi files. After which I finally got to play the mkv file with in sync audio although the video is now 1920 x 1088 h.264 when the original was 1920 x 1080 h.264. Is there way to bring it back to 1920 x 1080?

[Baldrick]

Use popcorn mkv audio converter or mkv2ac3.