I just signed up after searching on here for reviews of the FT1, and I feel I would be inclined to say change the source before changing the headphone or even the EQ. I don't have the Apple dongle, but my partner who sings and records guitar has a Scarlett Solo, and their Massdrop x Sennheiser HD 58X Jubilee, a pretty universally praised headphone sounded awful out of that source vs my own sources. I also just bought the FiiO FT1 and I can't say that I find it muddy or muffled out of my THX 788 streaming from Audirvana, I would say it sounds clear and detailed, but with a fairly small soundstage. I have not tried EQing it yet but I also don't feel much need to.