Game lagging and sound cracking at startup

[bright]

Hi everyone,
I am new to this site and I do hope its the right place for posting this subject. I've just installed The Sims 3 with several exp. packs, the game starts to lag and the sound cracking until I can hear anything but cracks and scrambled noises. Since my technical knowledge of computers is really low I'm wondering if its my laptop(Dell i7 intelcore) or something to do with the game?

[Angélique]

Lagging issues are very common when playing this game, but I don't remember anyone reporting that they're having sound distortions. Is it only in this game the sound is bad, or otherwise too?