@Hip has a thread around here that talks about his experience with that symptom which he was able to improve.
I'll try to think of where it is, but that might take me a bit.
It might be possible that something else is triggering your anhedonia? Or, you're absolutely correct.
One thing I have noticed: is if you're improving a bit, if you're gaining some energy or feeling less toxic and awful, this provides some energy for "other emotional states" to show up. I might feel a bit MORE depressed, or less motivated. It's an odd thing. But might be at play.
I've been a bit more bored recently, I'm usually too exhausted to be bored. So I take that as a bit of a sign of maybe some improvements.
But clearly, you need to figure this out if you can.