[Gelbster]

Maybe we went to the same concerts?
I have just been working on this issue using an Engine Ear, old style stethoscope and screwdriver. Even with the Engine Ear it requires lots of different positions, volumes,engine speeds to make an informed diagnosis. Even then, is it a lifter carrier issue or a lifter(s) ?
You need to discern the smallest changes in noise volume.pitch and frequency . You need to use both ear buds and really concentrate & repeat. Even using a smart phone microphone as close to the cam cover underneath the engine would be difficult in the early stages of lifter noise development.