[ACollins59]

I started shopping around for an inexpensive monitor controller and they aren't as inexpensive as you might think (at least not by my budgetary standards). Then it occurred to me: why not use my 4-channel headphone amp? I never use more than two sets of headphones at a time anyway. So I ran outputs 3/4 into the stereo input of my headphone amp (luckily I had a spare 2 mono to 1 stereo cable kicking around). Then I plugged my studio monitors into outputs 1 and 2, still leaving outputs 3 and 4 for headphones. Works perfectly. I don't know why I didn't think of this before. I feel kind of foolish, but at the same time I am happy to have everything working again the way I want it to.

Thank you for your suggestions, Ben. While I didn't follow your advice exactly, it did lead me to this solution.