So here's a quick Audio fix for the Audio in TES4 Oblivion using Crossover 23.7.1! Install the GOG.com version using a Windows 7 32-bit bottle, and following installation, enter winecfg for the Bottle. Inside winecfg, add the following libraries in the libraries Tab:
x3daudio1_6
x3daudio1_7
xaudio2_6
xaudio2_6
Then click "Apply" and "Okay"