I'll answer to my own question. The speakers are ok. Just the product is for the different target audience and a bit bigger space. I consulted it with two hi-fi studios in Zürich and in both cases they agree that the device is ok even in combination with my speakers. It is just for bigger space - too powerful for my usage. I have to choose different product to be able to set volume in smaller steps according my needs and expectations. Currently when using remote control it is enough to slightly touch volume up button two times to have music too loud. The situation is not better when manually turning the volume knob. I decided to return the product as it clearly does not fit my needs.