Since you mentioned the high volume problem, I think you have the first version of the IRV66 which had several connectivity problems and other issues, but the uncontrollable volume issue was the most obvious thing that most people noticed.
In 2015, Patrick Industries would replace these units with just about no questions asked. I believe all they required from me was my address and a credit card in case I didn’t send my old unit back to them within a month or so. They didn’t put a hold on my card for the cost of the unit. They covered all shipping costs.
I don’t know if a new unit will take care of the problems you describe, because I don’t really understand the technicalities of what you are talking about, but the new unit I received has no issues at all for my purposes. I actually like my IRV66.
In case you don’t have this, here is a link for the owner’s manual for the IRV66:
https://pdf.crutchfieldonline.com/Im...32/932RV66.PDF
Bruce