Thread: Es-8 and iPad Pro audio issues
I'm happy to help. Certainly had my fair share of head scratchers when I was getting going.
Seems like that ALM headphone module will be perfect for your needs. Personally I use a Befaco Outs V3 because I need the balanced 1/4" jacks, but if all you need is the headphone out then something like that would be overkill.
Another thing to consider, if you wanted a bit more from the ES-8 but didn't feel like going the ES-9 route there are some expanders for more ins/outs. I've got the ES-6/ ES-3 combo for 6 extra ins and 8 outs respectively. They work very well and have kept me satisfied enough with the ES-8 that I haven't really thought about upgrading to the ES-9.
Happy patching!