Johnny;
As the risk of sounding like a salesman, the Nolan comm systems provide a lot of flexibility and you essentially build up the systems capabilities by adding components (and $$ !!). Below is a link to Nolan's factory website that details the options (see hot buttons at bottom of the web page).
https://ncom.nolan.it/en/n-com/index.html
Essentially, the N103 has an input and output jack moulded in it, and Bluetooth capabilities if added. If you wanted to use your own earbuds vs. those built-in, don't see why you couldn't connect your device to the audio system and then use the hardwire output (multimedia cable) to your headphones or earbuds - not sure what you'd really gain, cause if you're looking for outstanding sound quality nothing I know of will provide that >100db of noise going on outside the helmet so the built-in stereo speakers work fine for listening to music, phone, etc.
My 2 cents worth. Enjoy.