HoMM3 HD is a mod (add-on) for the game Heroes of Might and Magic 3.

I couldn't find it on the website for the Russian megapack patch; I'm not quite sure what you mean.

http://sites.google.com/site/heroes3hd/rus/download
I opened the page in Opera, IE, and Firefox – the Russian megapack is immediately visible.

It allows the game to reproduce all sound effects in a parallel stream, which noticeably speeds up the game after installation. After installing, the end-of-turn music plays slowly and glitches.

Disable parallel sounds or the 44 kHz stereo patch:
Open HiRezData\HiRez.ini, find
No wait playing sounds = 1 and Music patch = 1, and change 1 to 0 in either or both, and save.
Let me know what solved the problem.