The system has a mini displayport on it - if you need to connect to HDMI on the TV, this will do it:

www.amazon.com/.../B003OC6LWM

The problem is, as I am sure you have found out by now, is the XPS mini to HDMI only supports video.  I just bought the XPS 12 and have run into not being able to get audio from the XPS to the TV.  Very frustrating!  I wouldn't have gone this route if I would have known this limitation beforehand.  :(  

I have since resolved this problem. Not sure why yours isn't working.

Make sure you have a cable that has mini display port on one end and HDMI (if you TV has it) on the other. The cable itself must be able to support audio.

When it's hooked up to the TV you have to go into your audio devices in the control centre and it should show you the TV as an option. Right click and designate it as the default. Should work.

Thanks for the guidance Hangmandan.  Yes, I have the mini display port on one end and the HDMI on the other end.  Not sure if the cable is made to support audio as I figured they all did.  Is there a way to be able to tell this and/or which one did you purchase?  And finally is the control center you write about in the 2nd paragraph in the Dell or in the TV?  

Again, thanks.

I buy all my cables online from Monoprice.

Look for Mini Displayport to HDMI with Audio support.

I don't know how to check if an existing cable supports audio.

Try right clicking on the speaker symbol on the bottom of the screen. Choose "Sounds". Then choose the tab that says "Playback". It should show the available options. If you're using the correct cable, it will show your TV as one of the options. Right click it and choose "Set as default".

It must be the cable then as the only thing that shows is a "Speakers" Realteck High Definition Audio - Default Device.  

Just to make sure we are talking about the same computer yours is the XPS 12 convertible, the one that the screen flips, correct? 

Thanks for the help, 

Bill

Yes. Same one.

Well I purchased a MiniDisplayPort to HDMI Converter with Audio, plugged it into the XPS 12 turned it on and nothing but video into the TV.  I right clicked the speaker, then Playback devices and nothing there but the Speakers icon with the green check.  I've rooted around trying to find other solutions but could find nothing.  Very frustrating.  Let me know if you have anymore clues.  BTW, Dell says the MiniDisplay does not support audio so I don't know what to think other than I would not have gone this route if the Mini actually doesn't support audio.  

Thanks,

Bill

All I can say is that audio works with mine. Don't know what else to tell you.

Hey thanks for all your help Hangmandan.  I finally got a cable that works, It has the mini connector and a usb connector coming together to make the HDMI connector.  So even though there are two cables I have to plug into the computer there is only one HDMI cable that carries both video and audio.  After an hour of talking with Dell they insist there isn't any audio coming through the mini so this may or may not be what you have.  Regardless, what I have now works for what I need it to do, I'm a happy camper other than I have three mini to HDMI cables now.  Again thanks for taking the time to help me through this problem.