that is very odd, i did this exact process with my w760 and everything worked fine. my recommendation to the people having trouble with their mics is to go into a2uploader, then to ifs/settings/acoustic and manually delete all the files

*FOR W760 ACOUSTICS TO WORK, THERE SHOULD BE 66 FILES*

So once you have manually removed all the files, try reuploading only the "W760 Acoustics by Richard" because i know for a fact that they 100% work. If your mic starts working after you have done this, then they uploading the MachIII acoustics afterwards. If the problem persists, then backup your contacts and media ect... from your phone and do a refirmware flash using SEUS.