Unable to enable microphone access

When I try to use Skype, I get the message that I need to enable the microphone. Under Privacy>Microphone> Skype is not listed as an app that has requested the use of the microphone. The only app listed is YouTube, and it is greyed out so that option can't be changed. I reset my privacy settings and now not even YouTube is showing. Also, I read a thread that said you could check to see if you currently have Settings > General > Restrictions > Microphone (under the 'privacy' heading) set to 'don't allow changes' - if you do then change it to 'allow changes' and see if Skype then shows in Settings > Privacy > Microphone. I did this but there is no “restictions” option under settings>general. Please help!