#its not a feanorian phone; it doesn't have the right letters for this

[revee-nyardil]

There's one headcanon some people (including me) have and it's that Maedhros renamed Thauron.

Sources I found say that the name could be either/both Quenya and Sindarin, but if Maedhros named him, I'm guessing it was Quenya (when did the Fëanorions learn Sindarin? I don't know if Maedhros even knew it).

If Maedhros named Thauron, in Quenya, he would have used the thorn (The root word is probably saura/thaura).

Additionally, Morgoth (and by extension, possibly Thauron) hates Fëanáro, so the thorn would make the name that much more annoying. Which was probably the goal.

Anyways, what I'm trying to say is:

If Maedhros renamed Mairon

And if Maedhros named him in Fëanorian Quenya

Then the name would properly be pronounced Thauron, not Sauron.