Flew the Guppy at AirTran for 7 years and we NEVER used the hot intercom. I KNOW I have some hearing loss because of it. Fortunately at SWA everyone and I mean EVERYONE uses the hot intercom. Thank goodness.

We don't all use the same headset per se, but we all use the hot intercom and that means I can keep both of my ear cups on. Surprisingly, the Telex 850 I used to wear at AT was LESS comfortable than my Bose A20s that I wear now.

The OP has legitimate concern. Flying the Guppy w/o ear protection will result in hearing loss.