Why does my audio no longer work?

My built in speakers no longer produce sound. In addition my built in microphone no longer detects sound. Also, the audio jack port, no longer seems to receive signal from external devices plugged into it. The only method I have found that allows me to hear audio from my laptop is by remotely connecting a blue tooth speaker or head phones. As well as using a non-aux cord to connect the laptop to another physical device with it's own speakers. I have already taken this to geek squad at best buy, and they ran a software check and it worked in store, but I am now still experiencing problems. Is this a hardware problem or a software problem?