Tube pre-amp pop

I am fixing to send this POS, namely SP16L to ARC for service. Just in vain, Does anybody knows why the pre-amp only POP in volume up and down after about 1/2 hour warm up and only POP from zero to 4 at the read-out level. Passing 4 level at the read-out on front panel, there is no POP. When I took them to the dealer, it did not POP since it wasn't barely warmed up.

Have you called ARC and spoken with Leonard already. I answered the question regarding the the LS3 owners pop in the other thread.That one may be due to DC offset in his amplifier,per ARC. Sounds like you may have a seperate issue. You can always contact Steve Huntley at his shop (Great american northern sound?) and ask him, He worked at ARC for years before going out on his own.

I went to the local dealer today, their unit also POP but not as loud as at my house. I asked the owner turn down all the music and now he can hear what I 've heard but at a smaller scale since their enviroment is noisy with all the gears running. I took their SP16 home and et voila the same BS pop when mute and noisy volume up and down at lower level. Their and mine both acts the same way, what can I say, either the SP16 is designed to be Pop and noisy on volume control or the public owns poorly designed gears except for those who owns all ARC gears. My 799.00 Onkyo receiver is operating dead quiet after all these years, no POP no scratchy volume up and down and it faithfully does its job in my garage. Is it the reality of hi-end industry. Your unit is noisy but it is normal as our spec. called for and there is nothing to be fixed. We have performed bench test your unit twice and it is as good as new. Thank you, guys. Such a good working ethics, such a good customer service and I vannot wait to unload this baby on used market.