which damping factor is better for my speakers?

HI, ( excuse some mistakes in writing, i´m a spanish speaker)
My question is.... I have a Nakamichi Pa 7 power amp and a pair of KEF ref. series 105-2 , but I´ve seen that i have to turn a lot the knob of the volume of the preamp(threshold fet one ) to hear as loud as I like to.
someone told me the dampin´factor for this amp is 60, but says that it has too much power for the speakers as they are too eficcient. i´m confused, above all if once while hearing at some high level ( not to break my ears ), the leds of both the power amp and speakers turned On !. Is this normal?
On the other hand , some times I hear a sound comming from the amp, like if a metalic piece would crash agaist other, Imagine you take a small screw and throw it on the surface of the amp. This is the sound . It happens almost 4 times in the period of an hour. Is this related with the increase of heat iside the machine ? or what?
Gustaty: Whoever is giving you advice regarding your amp being too powerful for use with your speakers, since they are "too efficient" is more confused than you are. As such, i would avoid asking them any further questions as they are only going to make things worse.

Judging from what you are telling us, it sounds as if something is wrong with the amp. You shouldn't have metal "clanging" sounds coming from within your amp under any conditions. I can't think of anything that would cause this to happen short of a noisy fan kicking off or on.

As far as having to really crank up the gain on the preamp, Kef's are typically not real efficient. With a decent level of drive from a typical line level source ( tuner, CD player, tape deck, etc... ), you should pretty much have a very reasonable listening level by the time that you hit 11 o'clock on the volume control. If your sources are slightly weak on output or you have a quiet recording, you might have to adjust the gain setting on the preamp up to about 12 o'clock or maybe even 1 o'clock on rare occasions. If you have to turn it up this high or higher all the time, something is wrong. Judging from what you've said here, my guess would be that your amp is going goofy. Hope this helps... Sean
Sean, your opening paragraph just about made me fall out of my chair.

I concur with Sean. I wouldnt think the "metallic clank" would be heating/cooling expansion sounds.

I would have the amp tested and serviced if need be.