I'm glad to hear you got the distortion issue resolved Agathe. The Merlin/Berning combo really requires a pre-amp to get the most out of it. I have tried it direct cd out to BAM to Berning. On all settings it was always clear but a bit too lean again, regardless of the feedback settings. As Bobby notes, a tube pre-amp will enable you to tailor the sound to your taste. I have lived with this combo for almost 10 years continuously and I can't overemphasize the importance of system matching to maximize what these two components together can realize. The Berning is so transparent and resolving it is susceptible to vibrations and RFI because of the high frequency used to carry the signal. Tubes also are important to get a desired result. There are plenty of threads on this amp and the Merlin/Berning combo that go into details concerning pretty much all you need to know.