Iam a newbie and i realise i may be doing something incredibly stupid here so dont laugh.
Whenever i plug my headphones un hd600's into an arcam 8 amplifier.
Sound still comes out the speakers.
WHY?

[shahedz]

this is quite common with most seperate amps. dont know why, but do you have a speaker swith, (usally turns on speaker set a or b on or both on , or both off) as you have to turn the speakers off, not sure if your Arcam has the speaker switches

[fathervic]

There is a speaker switch for the Alpha 8 but only for speaker set 2. From my recollection (it's been some time since I had mine) the speakers should cut off automatically when you plug in your 'phones. The easiest way to remedy this for now is (if you single wire your speakers that is) connect your speakers to set 2 and switch them off when you want to do some private listening.