Btw II what you don't read in the manual, only on Chinese forums: the MUB1 has 4 gain settings that have a huge impact on the sound. Forget about L(ow), sounds flat. M(edium) seems to be for line-out (as mentioned in the manual). The magic starts at H(igh), as it sounds way bigger/bolder. S(uper) sounds even bigger, but with a tiny bit of background noise (I have pretty sensitive IEMs).