Let me simplify the problem. This may help...

I have selected (in Cakewalk) preferences... Recording Device: Line in (Scarlett Solo)
Yet under track view, when I select a tracks in/out properties. Under "In", it doesn't list the Scarlett Solo. 

That is the problem. It's not the driver, otherwise Cakewalk wouldn't list it as an option in Preferences. The driver has worked fine up until the last month. I'm unwilling to rebuild a system that worked simply to get around not understanding the issue. 

If you can help. Please do. If you cannot help with THIS problem... please do not. 

MME Driver (non-negotiable)
Windows 10
Cakewalk Music Creator 6

I should probably add that this is ONLY affecting recording in Cakewalk. All other recording programs are working fine. hence why I'm unwilling to change drivers just because one program isn't on board. 

This isn't just one recording studio computer with one DAW. It's a versatile computer that serves many functions and other drivers don't play well with other programs. MME may be a last resort, but it's what I've got that works. If Cakewalk is the issue, it's cakewalk that gets cut.