Opening a H264 stream from DVR using VLC/FFmpeg

I've been tinkering with ITX's DVR for the past few days, trying to connect to its RTSP stream using the SDK that manufacturer provides.

The official syntax goes like this:

PLAY rtsp://192.168.100.134/live?Live_video_channel_mask=0x0000FFFF&Live_audio_channel_mask=0
x00000000&Iframe_only=0&Stream_index=2/ RTSP/1.0\r\n

Video channel mask declares the number of video channels one wants to see, e.g. if I wanted to see channel 06 the mask would be 0x00000020 (two LSB would be 0010 0000 = channel 6).

I am using ffmpeg and VLC trying to display streams. My syntax goes like this:

ffplay -analyzeduration 2147483647 -probesize 2147483647 -i rtsp://ADMIN:1234@192.168.1.25:554/live?Live_video_channel_mask=0x00000020&Live_audio_channel=0x00000000/RTSP/1.0

What I get however is the following message:

*[rtsp @ 02a24680] UDP timeout, retrying with TCPB sq=    0B f=0/0
[rtsp @ 02a24680] method PAUSE failed: 501 Not Implemented
[rtsp @ 02a24680] Could not find codec parameters for stream 0 (Video: h264): un
specified size
Consider increasing the value for the 'analyzeduration' and 'probesize' options
rtsp://ADMIN:1234@192.168.1.25:554/live?Live_video_channel_mask=0x00000020: could not find codec parameters*

I've sniffed packets from a WWW interface that is used to connect to the DVR, the RTSP syntax looks like this:

*rtsp://192.168.1.25/live?Live_video_channel_mask=0x000000ff&Live_audio_channel_mask=0x00000001&Live_iframe_only=0&Live_stream_index=0/*

When I try to replicate it in the FFmpeg, the DVR reboots.

VLC is also unable to display video properly - I can see codec parameters for a brief moment (DESCRIBE firing correctly, perhaps?), but the video itself is not decoded.

I have captured the RTSP packets as well:

https://www.dropbox.com/s/qzo7kc95mo7dq9o/RTSP_ITX.pcap

I have no clue what could be wrong with this one. Help, anyone?