it's always easy to cry "troll", "idiot" or "learn to use it" if somebody has a problem. Me too, i found lot of posts and threads here and elsewhere complaining about fizz and harshness. Perhaps not thousands, but a lot. And there are a lot of discussions why the modeled cabs sound like they sound. Why the use of the Highpass is recommended in every second thread here if there would be no fizz. I learned a bit to handle it but i never really understood why to need a highpass when using a modelled cab with a modelled mic.
Some people seem to ignore this fact for any reason and that's not more serious then complaing by opening a dozen of threads or not delivering detailed informations.
But i guess, some samples would be really helpful.
Perhaps it's not everybodies problem because perhaps not all Helixes are exactly the seme like they should, specially in the digital world: My box had the effect in an earlier software version, that it seemed sometimes to loose the cab. I switched from one preset (sound ok) to another preset and back and suddently it sounded like an amp without cab and mix sim. Restarting the unit solved the problem. And 'til today, it does'nt appear again in later software versions.
So if my Helix can do such things, others can do perhaps too and - more nasty - perhaps they can do even different mistakes.
So the thinking "If i can't reproduce the problem, nobody can have it" is perhaps thinking a bit too short - even in the digital world.