Tach, after a long break I report with a problem mentioned here several times with different MX5, which I have not found any solution for me in other forums. I have now made a change of timing belt and the above mentioned “sleep noises” are now also present with me. Years ago I had been through this and after that was nothing… all nice. Here again all steps to the current exchange / problem: – timing belt including rolls renewed by IL (Spannu ng only controlled by spring, or according to manual specifications again and for me i.o.) – new clamping spring original Mazda – water pump IL newly mounted – Simmerring crankshaft + camshafts renewed After assembly everything purrs as it should be until the engine is warm (cooling water and oil).. Then the “slip noise” begins.. Next step, straps Lima, servo and wapu off, Arregate do not run along.. Noise still unchanged. Thus only the tooth strap remains as a fault for me. . Next step, new clamping and deflection rollers installed by SKF and all attachments / cladding parts controlled on grinding tracks, the belts are tightened slightly differently.. NO change, When the engine is cold, everything is fine, when it is warm the noise starts again. It gets louder with increasing speed and I would say so from 2500-3000 Umdr. away or just goes down with the side noises.. Since this problem has already been discussed several times, is determined after all a I hope to say hello, Torsten.