I have a Yamaha P105 Digital Piano. Recently I bought a pair of Yamaha HS5 studio monitors and connected them to the P105. The high frequency tones in the grand piano mode are very distorted and do not come from the tweeter. All other modes(electri piano, strings, rock organ etc...) are crystal clear.
However when I connect my headphones to the P105 piano, all sounds in all modes(including the grand piano mode) are crystal clear for all the range of frequencies.
Can anyone suggest what might be wrong...?