(In reply to Jason Playne from comment #2)
> This is has just started effecting me too. Playing "Hellblade: Senuas
> Sacrifice" on steam (so steam play / radv / dxvk)
> 
> mesa via pkppa
> 
> kernel 5.1.15-050115-generic (ubuntu kernel ppa)
> libdrm-amdgpu1:amd64                2.4.98+git1906260630.4
> mesa-vulkan-drivers:amd64           19.2~git1906240730.3b6
> 
> this wasn't happening 2 days ago, now it happens consistantly

Sorry, its via the oibaf ppa.