I’m having the exact same issue. I can create a print with either the left or right extruder, but when I try to print a two-color print, I get the same result on layers where both extruders are used. As I see in your photo, when a layer uses a single extruder things seem to go back to normal. Did you get a fix for the issue? I was wondering if it had to do with heat up time on the extruders as they change in a layer. I’ve tried a lot of adjustments but no luck so far. LMK if you found the problem.