Maybe a pointless question, but do you have tube dampers on the LS25? I have a LS26 and hear no noise. Maybe the tubes need replaced, take small steps to solve the issue.
Possibly vibration dampers under the componet. Mine is on AQ Feet. Contact ARC they are very helpful on the phone, the challenge is reaching someone on the phone as they are very busy. If you are buying new tubes look for the 6H30-DR, I have found them to sound better than the ARC OEM tube.
Possibly vibration dampers under the componet. Mine is on AQ Feet. Contact ARC they are very helpful on the phone, the challenge is reaching someone on the phone as they are very busy. If you are buying new tubes look for the 6H30-DR, I have found them to sound better than the ARC OEM tube.