Hi there, 
I am running OS X 10.11.5 El Capitan on my E6230 with IDT 92HD93 Soundchip. 
  
I installed VoodooHDA288, AppleHDA and ApplaHDA_IDT. 
The Speakers themselves are working with VoodooHDA. 
  
Problem: When I adjust the volume with the hardware-keys, OS X shows the onscreen change of the volume, but it is not transferred to the speakers - I cannot control the speaker volume with the buttons or software, it is always on 100%. 
  
Thanks for your help, appreciate it!