I assume you are probably talking about the Windows native audio services, so....
type
services.msc
into the search or run dialog box and hit enter.
Scoll as needed and find
Multimedia Class Scheduler
Windows Audio
Windows Audio Endpoint Builder
Double click them and make sure their respective "Startup Type" is set to Automatic
Additonally you may want to search the event viewer to see if there are any error logs being reported pertaining to audio. Expand Windows Logs, check application and system. A quick and dirty right click and find "audio" might get you started. Perhaps a third party audio service from another vendor might be conflicting.