Hmm… As for the reverb 'm convinced it is some setting because the INS/MON is the exact and one and only setting which entire functionality is to monitor or track/record the DSP effects. I’m assuming none of the other DSP effects can be recorded neither right?
What DAW are you using btw?
Still the loopback function should/can only be used for streaming. I take it you want to record in your DAW someday too so we should find a solution. Since loopback weirdly works it shoudl definitely be another setting but which one…?
You probably know already but just be sure to turn on dspMixFX before opening your DAW (unless you use Cubase in which case it’s integrated and you should configure it differently (hence my question about your DAW).
Another thing I was thinking about is the MIX you select (1 or 2) for headphones as in maybe you listen to MIX2 while recording MIX1. I’'m not even sure this is possible though but really INS.FX should’ve fixed the issue.
Maybe you can post a sceenshot of your settings in dspMixFX and the routing in your DAW?
Btw. Steinberg support really sucks! Hard to reach since they’re always on fairs (happend twice with me) and you get generic answers where they basically copy/paste from the manual. Also this forum needs active mods. Don’t want to be bashing since their products are usually awesome but this is another truth as well…