Surface noise

Well, it's at least 4 or 5 years old. I wish I could take a stab at how many hours, but I'm afraid I wouldn't be close. Maybe 1,000 hours tops? I do have another older Grado to try and I will this weekend when I get home. Just to describe the sound I hear, it is kind of a hollow sound, not scratchy, and only in between song tracks at higher volumes. Maybe I'm making too much out of this?

Is it a Whooshing sound? What is your other equipment. could it be tube rush? Does it change in pitch? perhaps bearing noise, have you lubed it?

Not really a whooshing sound. I've also changed the phono section tubes around with no difference (Rogue Audio 66 Magnum pre-amp). Your comment about the bearing noise sounds interesting. The tonearm does seem to deliver a decent amount of noise through the system when I tap on it with my finger. I think that's why I've described it as kind of a hollow sound, but clearly the sound is of the needle running over the flat vinyl in between tracks when I have the volume up pretty high. I have not done any kind of lubrication, etc to the table. The last time it was gone through was by Soundsmith over 10 years ago. What should I try to lubricate and how?

Have you done anything to load the cartridge? Grados seem to like about 8000-12,000 ohms.

Loading the cartridge? Now you've lost me.