Yamaha pcs, pst,sst Styles. There have been no comments about some of the new styles in the PSR2000 & CVP209. A number of Styles have the extensions. pst or sst or pcs. If these extensions are renamed with .sty they all load into the 9000 & 9000Pro. Some however produce unusual results when a minor or a seventh chords are played. Can anyone put more light on this subject?