Had this happen 3 times now since ownership.

Firstly the LANDROVER logo that appears on the SATNAV screen on start up stays on and doesnt go onto the menu screen, then when you switch the radio on the radio screen intro comes on and then the radio switches itself off. The only remedy was to switch off ans restart. Now - 2017 BMW X3 M Sport Carbon Black
Gone - 2014 BMW X3 M Sport Space Grey, faultless!
Gone - 2011 Freelander 2 SD4 HSE Bali Blue with xenons
Gone - 2008 Freelander 2 TD4 HSE Rimini Red with bodykit

Had similar: all the display is there, will change from radio to CD, etc. but no sound at all. Same remedy as you; switch off ignition and switch on again. Happened no more than six times in seven months.

DT

This is a known problem and requires a software download to fix. Mine used to do it if I got in and inserted the key fob quickly. Now fixed with trip to dealer and and plug into their magic machine.