Recently I had the same issue (a coincidence!) with the words: “At The”.
Same result.
Just an observation:-
Thinking about this example (and trying to say it out loud), the two plosives are difficult to pronounce, at least for me, either I have to slow down and emphasise the leading 't or drop it altogether and say “a-the”.
It doesn’t surprise me that SynthV struggles!
Yeah I would say that’s because the words end and start with a T. If you were saying At The Top you would expect the T of Top to sound surely?