I'll just post this here.

Among the many irritating features of the pc version of dmc 3 is the fact that the sound engine causes terrible slowdowns. The quick way to fix this is removing the sound folder entirely, but that's like killing a fly with a bazooka. If you actually intend to play the game, it is possible to remove certain key sound files which cause the slowdowns.
Here's a little batch utility I made which allows you to do this quickely and painlessly. It makes a backup, then remove the files based on a user-supplied list.

SoundRemover

And here's the list. Copy-paste it into a text file and name it list.txt.
Place both the batch utility and the list in your gamefolder, then run it.
This will remove most off the mid-level battle music and other troublesome ones, but will leave boss-battle music,cutscene sound, ect. If you get any slowdowns, tell me precisely where and I'll update the list. Probably.

Battle_01.bin
Battle_01b.bin
Battle_03.bin
Battle_05.bin
Battle_06.bin
Battle_07.bin
Battle_08.bin
Boss_01b.bin
Boss_02b.bin
Boss_03b.bin
Boss_04b.bin
Boss_05b.bin
Boss_06b.bin
Boss_08b.bin
Jester.bin
Jikushinzou.bin
Kaze_01.bin
Kaze_02.bin
Kaze_03.bin
Kaze_04.bin
Kaze_05.bin
Kaze_06.bin
Maguma.bin
Mizu_01.bin
Mizu_02.bin
m_demo_04_004.bin
m_demo_04_004v.bin
m_demo_09_003.bin
m_demo_09_003v.bin
m_demo_10_002.bin
m_demo_10_002v.bin
m_demo_15_001.bin
m_demo_15_001v.bin
m_demo_19_001.bin
m_demo_19_016.bin
Nausica.bin
Room_01.bin
Stage_01.bin
Stage_02.bin
Stage_02b.bin
Stage_03.bin
Stage_04.bin
Stage_04b.bin
Stage_05.bin
Stage_05b.bin
Stage_06.bin
Stage_07.bin
Stage_08.bin
Stage_09.bin
T_bossb.bin