Hi All,
There are a few posts on the forum for this already but I performed an in-depth investigation as this issue affects me now as well.
So I am hoping to create a thread where we can all discuss and exchange information, and if possible find a workaround or solution.
What happened to me:
Simple, I upgraded my computer from a 7th Gen i7 8086K to the latest 15th Gen Core Ultra 285k.
I was using AXR4T with my old build without any issues.
Motherboard: Gigabyte Z370-XP-SLI
CPU: Intel i7 8086K
Thunderbolt PCIE card: GC-TITAN RIDGE Thunderbolt 3
(As my motherboard doesn’t offer onboard Thunderbolt connectivity, a PCIE card was required. These cards use internal wiring to connect to a Thunderbolt header that NEEDS to exist on the motherboard)
Adapter: StarTech Thunderbolt 3 to Thunderbolt 2 Adapter
(This was required to convert the TB2 connectivity from AXR4T to TB3 to connect to the Titan Ridge.)
Inevitably though, like everyone will have to at some point, I had to upgrade. Trusting Gigabyte for years I went with one of their setups.
Motherboard: Gigabyte Z890 Aorus Master
CPU: Intel Core Ultra 9 285K
Adapter: StarTech Thunderbolt 3 to Thunderbolt 2 Adapter
(This was required to convert the TB2 connectivity from AXR4T to TB4 to connect to the Z890.)
Following the upgrade, my computer stopped recognising AXR4T, as if it was never there. Now, let’s get to the issue.
What is the problem:
In one word? Intel.
It appears there was a critical security vulnerability with Thunderbolt 1 & 2 protocols which would allow a malicious attacker to obtain access, or even damage, your device by plugging an unauthorised and malicious Thunderbolt device to your computer. That means that that person NEEDS to be physically next to your computer.
While the security vulnerability is definitely concerning especially for potential attacks on data centres by infiltrators or publicly accessible computers, it makes absolutely no sense for people who work in a confined environment like we do.
With that in mind, I do not understand why Intel simply does not give people the option to enable backward compatibility with Thunderbolt 1 & 2 at their own risk.
I also don’t understand why they did not patch (fix forward) the vulnerability, rather than dropping the compatibility altogether.
It’s worth mentioning that this affects the Intel platform only. If you are on a Mac machine, you won’t have any problems with backwards compatibility.
My technical understanding:
Thunderbolt 4 when it first came out WAS backwards compatible.
So motherboards that had Thunderbolt 4 connectivity, with an old version of their BIOS, could and can use Thunderbolt 1 & 2 devices.
BIOS updates also carry the Thunderbolt firmware version within their package. This means if you upgrade your BIOS and it happens to install a Thunderbolt firmware higher than NVM31, you are done.
This is why you might see Thunderbolt 4 being backwards compatible on motherboards with Intel chipsets from B/H/Z6xx or earlier. B/H/Z7xx and B/H/Z8xx already come with the newer version of the Thunderbolt firmware as you purchase them which creates an issue because then how are you going to upgrade your workstation? This is something that will have to happen at some point!
To make things worse, these newer motherboards don’t always have a Thunderbolt header on them (Z890 doesn’t) so trying to connect a PCIE Thunderbolt 3 card won’t work!
It’s also important to note that once you upgrade your BIOS, there is no way back. You cannot downgrade. The only exception I believe was ASUS which released a tool to downgrade the version for some of their motherboard models but I believe it was taken down shortly after. I am not an ASUS user so I am not entirely sure of the full story here.
What now?
Well, my friends, the news is not great 
Personally, I have built my whole studio around the AXR4T. I have paired it with a Ferrofish Pulse 16 to get extra connectivity and all my 500 series outboard gear, my Kemper, my summing mixer and preamps are now useless. I am in the region of £10000 gear that I can’t use because they all connect via the AXR4T and that doesn’t work.
I have a backup USB2.0 Audio interface that I can use for now but it has nowhere near the same connectivity as AXR4T. This means I still cannot use any outboard equipment but at least I can continue mixing/mastering with plugins; but I know that not many people have the luxury of having a backup audio interface sitting around (I was using it to add additional preamps to the AXR4T).
However, I still want to be able to use the connectivity AXR4T offers but also these amazing transparent preamps with the Neve Silk on them.
The solution:
- For AXR4T users, I would urge Steinberg (although not their fault this happened) to help us by offering an expansion slot swap to convert AXR4T to an AXR4U. I would be more than happy to pay for an upgrade like that and I really don’t want to be forced to move away from my AXR4 (at least not at this point)
- Overall for Thunderbolt users, I really don’t know what can be done. Can we start a petition against Intel to give us an option to enable backwards compatibility at our own risk? Will they listen to us? I suspect the audio community is quite small in comparison to the standard computer users who will probably not even notice this issue however the impact is huge for many of us - Apart from the equipment not working, we are losing time troubleshooting and also this impacts our running projects and is a risk to client reputation
- On top of the above, potentially reaching out to our motherboard vendors could help if they were able to offer a solution to downgrade the Thunderbolt version back to NVM31 somehow but I am sure there is no guarantee they will do it.
Thanks for reading.
Thoughts?
