[Far Cry 5] Weird rhythmic and persistent pattern of stuttering

[ghost]

GPU: AMD Radeon RX 7900 XTX
CPU: AMD Ryzen 7 7800X3D
RAM: 32 GB DDR5 6000Mhz
OS: Arch Linux, latest mesa and vulkan-radeon drivers, 6.12.8-zen kernel.
Proton 9.0.4, also tried Expiremental, Hotfix and GE version.
Latest DXVK 2.5.1

For some reason, this game experiences strange rhythmic stutters at random intervals, lasting for a few seconds and disrupting immersion.

This isn't caused by autosave stuttering or hardware limitations – I have a high-end AMD gaming PC, and the game would run perfectly smoothly if not for these anomalous hiccups. Overall, it performs much better and smoother than on Windows, but these stutters negatively affect the experience when they occur.

I've tried everything, from disabling overlays to adjusting various graphics settings and testing different Proton versions.
I suspect the issue might be related to Proton or DXVK, or some underlying game processes.
Here is a video demonstrating the issue:
https://youtu.be/cW7KSzWTx3E
(I fast-traveled to the same location multiple times, and each time, the same stutter pattern appeared. This also happens randomly in other locations and while traveling.)

Additionally, here's another video from a different user on Steam Deck (stutters appear at 2:26 and 4:25):
https://www.youtube.com/watch?v=yz8B-INmpMw

You can clearly see these are the exact same rhythmic stutters.

This issue seems to have appeared recently, as I haven't noticed these stutters in benchmark videos prior to 2024.

[doitsujin]

These kinds of problems are hardly actionable, definitely needs more info:

• if this is a recent regression, do DXVK 2.4.1 or 2.2 work?
• Does the HUD (DXVK_HUD=full) show anything weird that isn't already obvious from Mangohud?