Yes, the sore throat went away for me after a week or so (I think - it was several years ago) My voice came back slowly. I remember using a lot of honey with a bit of lemon to soothe things. My friend is a musician, and he cautioned me not to "force" anything as far as my voice - to let things heal naturally.
Many others here have reported loss of voice with the Tobramycin - as far as I know, they all healed.
If things don't begin to feel better day-by-day, be sure to contact your doc to have a look at your throat.
Sue