Anybody have this HD model?

[Steve Snow]

The only problem I've found with the portable Insignia HD radio is the
headphone amplifier which is a little weak and the output impedance is kind
of high; no big problem for today's standard headphones but don't try to
drive your old Koss phones or one of those cassette adapters.  They are too
close to speaker impedance and the output drops down in volume and gets very
thin.

This is reminiscent of Apple's problems with the early iPods where the
design had to be beefed up for later versions.