Audio Research deemed not an essential business was closed down for a significant amount of time. I believe they're open again. I believe they had people working from their homes . Shipping I'm sure suffered. I'm sure they have a shipping backlog . I'm surprised you didn't get a response. If it was me I'd try again they're pretty good with customer service .
What is up with Audio Research during the pandemic?
I ordered a set of tubes for my ARC Ref 3 line stage on May 4, 2020. So far, no tubes, no tracking number, and no contact initiated by ARC. I did get an email response last week from them saying that they were "... working on getting caught up in the shipping department and have not yet shipped your tubes." This post is not to hassle ARC in the midst of a crisis. My hope is that all there are safe and well. Many "non-essential" businesses are struggling and frankly, I want to do all I can to support them. Music has been a wonderful source of comfort and enjoyment for me, now more than ever. I can wait, but I would feel better if I knew that the ARC folks were doing OK.