No, Krash, I do not have that problem. DTS plays fine for me through the internal speakers. I tested this with MKV files containing DTS streams over DLNA, and verified that the TV was indeed receiving DTS sound by opening the 'info' panel during playback. (I also needed to change the sound out option to Internal Speaker, but I'll assume you did that too. 😀)
Gurnaam, I was thinking the same thing about compatibility (and why not? the published WebOS 3.5 compatibility listing is pretty long), and I had high hopes. There are some fairly new video codecs supported, which is why I was so surprised that my set was having difficulty with long-standard audio codecs like AC-3/DD and AAC.
Do I know what's happening? No, not for certain. To be honest, the specific issue that you are noticing seems a little bit different from mine: for you, it occurs during pause, and some sound isn't playing at all. I would be interested to hear about the specific file types you are trying to play and what the rest of your setup looks like (optical or HDMI? Receiver or Soundbar? Age of other components? etc...). On my set, I just notice poor quality audio during playback from certain AAC and DD 5.1 sources that I know are fine.