I suppose you're using TataSKY HD.
All these Drama/Soap Opera channels don't have much scope for Dolby Digital 5.1 sound. Most of them are only serials with rare background score.
Zee HD originally doesn't provide 5.1 DD sound. Airtel provides only Stereo sound on it. TataSky seems to have enabled fake 5.1 DD sound on Zee TV, resulting a much inferior sound than the original Stereo sound.
Airtel has screwed the sound of this channel, hence no proper surround sound. Rear speakers sounds very low with sort of unnatural sound.
However, Tata SKY provides much better sound on all the 4 Star HD channels.
These channels don't have all the programs in 5.1 sound. Most of them are in Stereo only, but what these DTH providers have done is...they seem to enable fake 5.1 sound, hence it looks quite unnatural.
The point is...all the DTH providers should telecast the original audio and video provided by the channel broadcaster, without downgrading the original bit rate of the channel's audio/video. But customers are always at mercy of these DTH providers !!
Fake 5.1 OMG !!! Now this is getting more interesting. I've seen somewhere in this forum that Sun HD is the only channel which provides the original audio and video of the broadcaster