Xtrend ET10K, 2 x satellite tuners 28.2 (Sky FTA), 2 x hybrid (UK Freeview), Zgemma H9S (satellite)
Blu-ray (12-05-15)
A booster will not fail on just 1 MUX from around 6 off you are probably receiving. The booster is wide band amplifier without any knowledge of what is being passed through it - it just amplifies input signals irrespective of their DTV content.
If you know your transmitter just google for "transmitter name freeview" and the first or second hit will be a transmitter information site with details of engineering work which may explain the loss of a MUX (reduced power whilst being maintained etc.).
Have you actaully lost the channels or just the EGP for those channels?
Xtrend ET10K, 2 x satellite tuners 28.2 (Sky FTA), 2 x hybrid (UK Freeview), Zgemma H9S (satellite)