There are strangenesses in behavior of mine Burson HA-160D. At switching-on and shut-down in earphones small chinks as at loudness regulation chinks are audible at each step of the attenuator (a step - click) which loudness depends on the installed loudness are audible. It is normal? Or spoilage?

I bought Burson Ha-160D. I received it in two weeks. Everything was alright! Many thanks Drew!