Hi guys, Recently I bought a budget music system to improve sound quality. I bought a onkyo a9010 receiver in combination with mission LX2 speakers, as they both seemed to have good quality for the money. I use this setup to listen music on spotify with a google chrome cast audio. In general I'm very pleased with the sound coming from this system. However, there is one thing that annoys me quite a bit. When there is playing nothing but just a piano there is some kind of distortion making the sound of the piano very bad to listen too. I first noticed this from the sounds in the playstation4 menu. Then I decided to listen to some classical tracks on spotify. Only a piano playing sounds distorted even at normal levels. This does not happen when listening to guitar solo's or even violin solo's. I listened the same songs at other peoples music system (not in the same room as mine) and the songs sound just perfectly fine. As this does not happen with other instruments and it happens in both speakers it seems to me that its not a speaker problem? Has someone experienced this before, and is there a way to solve this? Hope someone can help me out (one of the song that it happens very clearly is Beethoven No, 14 "Moonlight" in C-sharp played by Paul Lewis).