The Bluthner piano, when it's set on the "Vintage Decca Tree", has an strong "vibration" in the tone. It's a tremolo, actually, in a regular pattern. Two big dips in volume, then two more after a brief pause, and so on. This happens on the Room-Mix Vintage preset as well as the Surround to Stereo Downmix Vintage preset.
I've checked all the other presets, and they are all OK. I have also checked all my other Synchron pianos (Bosendorfer Imperial, Yamaha CFX, Bosendorfer 280VC, Fazioli F308, Fazioli F212, and the Steinway D-274). None of them have this problem.
Any idea of what's going on? Is a correction in the works? I like the Vintage preset, but it's unusable.