How can Hyperthyroidism affect one's voice?

[VoxLife]

I suffer from weak, breathy, high-pitched voice with no resonance or projection or loudness.
It's not just vocal habits, it's just that my vocal folds don't vibrate properly to produce sound.

My father has had congenital goiter, (thyroid enlargement) and had surgery done to remove thyroid. (thyroidectomy)
I'm wondering if I have hyperthyroidism too and if this is the cause. I have symptoms of hyperthyroidism now that I looked into it so...
I've been to 4 ENT doctors and 3 voice therapists with MTD diagnosis or no diagnosis, as they say my voice looks and sounds okay, but I know very well it doesn't.
It's only been a week I discovered about this potential thyroid issue I might have.

My siblings have the exact same voice issue as I do.
My father and his siblings had all thyroid issue- goiter so it's possible we all inherited this from our dad.

[specialmom]

Thyroid issues impact our hormones and hormones can impact our voice. Was your father ever treated and did things go back to normal?