I am no audio expert, but as far as I can tell this preamp is in great working condition: All ports, switches, and dials have been tested to be operational. Some of them have unusual audio effects when I tested them, but that could be because they are for types of input that I was not testing them with. But buy with confidence: Should it turn out that something is amiss, returns with free shipping are accepted within 30 days for any reason.
The included headphones are in great working order as well, with clear sound and no damage to the flexible covers. Both the preamp and headphones do show some minor cosmetic scuffing, dust, and other general signs of age and use, but nothing that affects their function or integrity.