McIntosh MA 2275 - Headphone Jack Debacle

Just purchased an McIntosh 2275 Integrated tube amp. Imagine my suprise when I discovered that the speakers still play when the headphones are connected to the amp.

I asked my retailer if I was doing something wrong, he called McIntosh and they repsonded by saying that a) I was the first person to discover this and b) they have no solution to the problem as they never made any provision for this functionality. Makes we wonder why they even bothered to put a headphone jack on the unit.

Any recomendations for headphone amps?
Will the 'mute' switch permit you to listen through headphones while disconnecting the speakers?
Mute swith will enable listening to headpones but without any volume control.
When I use headphones with my MA2275 with the speakers muted I can adjust the volume to the headphones.
From the manual: Mute: Press the MUTE Push-button to mute audio at the Loudspeaker and Headphone Outputs. Press MUTE a second time to unmute audio.

Note the "and Headphone Outputs". I find this very odd. Isn't the whole point of headphones in a home setting (not a studio or other professional application) to listen with no sound coming out of the speakers, to accomodate late-night listening, for example?

I came very close to buying this amp, I think it is one of the coolest integrated amps out there, but as an apartment dweller and late-night listener this would be a deal-breaker for me. But Kbell says that the headphones can be used with speakers muted, so what is up??
Kbell is techically correct. There is some level of volume control but you really don't get much volume off the headphones - about 25% of what you should be gettting.
I took another look at the manual (on the McIntosh Website) and the part I quoted is from the remote control description. Elsewhere it says the the front panel mute mutes the loudspeaker outputs. So apparently the mute on the remote control and the mute on the front panel functions differently.

If you are not getting the volume you want, could it be that the McIntosh doesn't like the impedance of the headphones? High-impedance headphones may not sound as loud?
I owned one of these a few years ago and noticed this issue as well, but being I was just "playing" with the 'phones with no intentions of using them regularly I never pursued further.
I just took care of the problem and purchased a Grado headphone amp!