Firefly flickering frequently in Synapse 3.0

I'm using choma spectrum cycling on a Blackwidow, Firefly, and Deathadder V2 through Synapse 3.0. Like many users reported, the Firefly flickers frequently (most often when it reaches blue). I saw that some "fixes" say that Synapse 2.0 makes it go away, but Deathadder V2 doesn't get detected in 2.0. Does anyone know how to fix this? Either for Firefly to stop flickering in 3.0 or for Deathadder V2 to be recognised in 2.0.