We only support transparent addresses and we do not support ZCash z-addresses at this time.
Changing of addresses within Jaxx Liberty is normal and part of our safety features. Jaxx Liberty is an HD (hierarchical deterministic) wallet, which means it generates a new address every time you send/receive digital assets to/from your Jaxx wallet as a way of keeping your balance private. You can use any of your previous addresses to receive digital assets.
Please do not point your ZEC mining rewards to Jaxx Liberty, as we are a lightweight wallet that is not designed to receive mining payouts. We do not recommend pointing any mining rig payouts to Jaxx Liberty as it may cause issues on your end as well as potentially cause issues on our end.