[SiriusHardware]

While the assumption re: 4.43MHz crystals is true - they were used in their millions in colour TVs at one time, so very widely made and therefore cheap - I'm fairly sure programs like Digital Clock - where software timing was used for the clock to run at the right speed - and 'Music Box' - where software timing was used to produce the right note pitches - worked properly with the original 4.43MHz clock.

Of course, I could just be completely tone deaf.