Fix a loud sound pop introduced in commit f098a58ca3ae27d39932fd5cc2b7f6c677ee8cba caused by rewinding the Direct Sound write offset.

This will fix the sound in games that use Direct Sound, as well as, with commit f098a58ca3ae27d39932fd5cc2b7f6c677ee8cba, the synchronisation in at least the following games:
* Bomberman Story, Japan, and Bomberman Tournament, USA;
* Castlevania games;
* Donkey Kong Country games;
* Dr. Mario & Panel de Pon, Japan;
* Earthworm Jim games;
* Final Fantasy games;
* Golden Sun games;
* Kurukuru Kururin;
* Mario Golf: Advance Tour;
* Mario Kart: Super Circuit;
* Mario Tennis: Power Tour;
* Mega Man Battle Network games, US/Europe, and Rockman.EXE games, Japan;
* Pokémon games, US/Europe, and Pocket Monsters games, Japan;
* Puyo Pop, US, Puyo Pop Fever, Europe, and Puyo Puyo Fever, Japan;
* Sonic Advance games;
* Super Mario Advance games;
* Yu-Gi-Oh! games.
GCW Zero: #ifdef SOUND_TO_FILE, write ~/.gpsp/trace.wav containing the audio rendered to the hardware.