R34 neo solid lifter noise

[Samyr34]

Hi guys, have a noise coming from the motor, not sure if lifters. Sounds like a knocking/ticking sound only at idle, weirdly kind of goes away when you rev it. When cold start right at the start the noise isn’t there only comes on after about 2-3 minutes of warming up. Once car is up to temperature the noise subsides slightly but still evident. I have kelford cams with valve springs and retainers. On e85 aswell. Refreshed motor.
 Oils only about 1000km old. 

[GTSBoy]

Use a piece of garden hose as a stethoscope to narrow down where the noise originates. Could be from the timing belt area/VCT actuator, or cam lobe slap on lifter, or something else.