I don’t have a V myself, but I can potentially offer some insight to the speaker issue.
With audio design, you have the speaker itself, and the acoustic design, or how the sound echoes and resonates inside the device behind the speaker.
Samsung has access to good speakers, and has experienced engineers to design the acoustic cavities to make the most of those speakers in the small device.
The V has speakers which, are on paper, really good. But the acoustic design isn’t as good due to lack of experience, and potentially even the people designing the audio solution not realising the importance of acoustics. And acoustics is a pretty complex thing to get right and do well. Especially in a thin device like a phone or tablet, and is the part of the reason why TV speakers have been getting progressively worse over the years as TVs get thinner.
But as for the sync issue, that’s a really weird and shitty issue that can hopefully be fixed with a future software or driver update… Though it could be a decoding issue, or an issue with your media player. Does this just happen with one program, or all of them? Because if it only happens, with, say, Windows Media Player, you may be able to fix it by switching players to something like VLC, or any other alternative.