So I got a Genesis Model 1 and 3 games that weren't terribly interesting to me, but it was cheap enough, and I got Sonic 1 separately which I am terrible at but getting better.

One thing I noticed is that the headphone out on the front of the system has a good amount of noise. You can't hear it during gameplay when there's music or sound effects playing, but any time there's a intermission screen with no audio playing it's pretty obvious. I also noticed some occasional popping sounds when sound effects play in games.

When playing through the TV with composite, using the headphone jack on the TV, I didn't hear either, although I didn't really try listening for the occasional popping sounds.

I am using an official Sega Model 1 power supply that I originally purchased for my Super Famicom. The one that came with the unit was an aftermarket 3rd party supply.

Is this normal? Is it possible that the TV is filtering out noise on the composite output?