Thanks everyone for the useful answers! One of my pedals has only midi in so having the ONE as last it's not an option. I got for the moment a midi patch bay, I did buy an H9 and then I'll wait a little bit to see if they release the fix. Maybe I'll keep both! This is the first time with Line 6 I have ANY issue, and I'm old enough to have owned the first POD lol, and now I have 4 of their Helix products.
In regards to datacommando's answer: This is a forum, I'm looking for answers and I can share frustration about a Line 6 product, that's not against the rules. In the past I opened tickets but as another user mentioned, they politely ignore what they can't fix or not ready to fix. As an end user my opinion is that a company like Line 6/Yamaha putting out a product that's clearly marketed for traditional pedalboards with issues in a very important function like midi thru chain (today most use a midi switcher and midi pedals for the convenience of program changes in patches) it's not a small bug, like some other reverb decay settings or similar, it's a crippling one. And I do not think I'm the only one with this issue. So, maybe I'm mistaken, but I don't get your sarcastic answer, that's not helping anyone. Also, chastising me (a regular user) really seems out of place and straight out rude, especially when you point out it's my first comment. But then again, maybe I misunderstand the tone in the written message? :)