Bir adım daha yakın! =one step closer

Bilgisayarımın ses şimdi sabittir! (I think you wanted to say, "the sound of my computer is fixed now". Unfortunately, "sabit" means "fixed, constant". In order to say "to fix, to solve", you can use the verb "çözmek".  You could say "Bilgisayarımın ses sorununu çözdüm, meaning "I have solved the sound problem of my computer")

Geriye kalan tek şey: bir mikrofon olsun.
The only remaining thing: a microphone