From anyone else they would have sounded insincere.
But the president has changed his mind about economic policy so often that now his officials sound insincere even when they speak the plain truth.
That's why his voice sounds so insincere to me, it's because my subconscious hates me for doing it to him.
But it sometimes can make matters worse because you may end up sounding insincere.
This passage may sound slightly insincere to some ears, but it doesn't to mine.
I tell her some things are better, actually, and quickly try to figure out what without sounding insincere.
Nothing that doesn't sound judgmental or insincere.
Then, because he felt he had sounded insincere and didn't want to leave her without anything, he said, "You've got pretty legs."
My words sounded insincere, even to me.
He tried to form the words of an apology, but everything sounded too stilted and insincere.