The issue occurs with Source Samples above 32. Anything above 32 source samples will cause a huge frame drop/stutter in the game. The higher the setting the faster it happens. 128 sound sources lag occurs faster and lasts longer than 96 and so on. 32 seems to dissolve the issue. Please fix. I used 128 in ARMA 2 with no problems.
Easy to reproduce with explosions...A164 GAU or Anti Air Armor.