Imac to Naim Uniti 2

You can always invest in an Apple Airplay unit with an optical cable to your Uniti2 (assuming a direct optical cable connection is not an option).  In the System Settings you can change your speaker output from the internals to “Airplay” which will allow you to send the audio to your Uniti2.

Regards

Macbook pro and IMACS have optical outs which are in the headphone jack.

then you need a special cable...

otherwise you can always buy a USB - SPDIF interface. 

some are available for little money, the best always cost more, but with major sonic benefits (check out audiophilleo, the same one used in the Naim DAC V1)

If you load radio three on the iradio then press down on the front display pad you can find a load of podcasts etc perhaps your concert is in there?

Thanks for your help but I will buy the cheapest iPad as I think it might be the best bet at the end of the day.

you can get a toslink cable for much cheaper. you don't need anything fancy, as the stream is not high resolution. But, as garyi says, you probably already have the capability to get the radio stream already inside your uniti.  nothing wrong with an excuse to get an iPad though ;-)

Thanks mutterback