Sonic Chronicles was going to have remixes of old Sonic tunes, but the Sonic 1 and Sonic 2 soundtracks were composed by the band Dreams Come True, which means that to actually use any songs from those games they'd have to pay royalities, so some confusion happened with them and SEGA a few months before releasing the game, that SEGA didn't want to pay royalities to them.
They ended up re-arranging other Sonic tracks anyway by stealing MIDIs from the internet and making rushed compositions because of that.
This sort of thing also happened with Sonic Spinball. Howard Drossin used the jingle from the Sonic 1 title screen to make the title screen song for Sonic Spinball, making this americanized, guitar-like re-arrangement of it. On the day of the release, Yasuhara contacted him saying he had two hours to compose another title screen jingle, because they'd have to pay royalities to actually use that song.
They ended up re-arranging other Sonic tracks anyway by stealing MIDIs from the internet and making rushed compositions because of that.
This sort of thing also happened with Sonic Spinball. Howard Drossin used the jingle from the Sonic 1 title screen to make the title screen song for Sonic Spinball, making this americanized, guitar-like re-arrangement of it. On the day of the release, Yasuhara contacted him saying he had two hours to compose another title screen jingle, because they'd have to pay royalities to actually use that song.