The inflection here is a little strange. When I do the whole sentence it sounds like 'спасибо' but when I just listen to the word it sounds like 'спасибо.' The stress seems to shift.
The italics made it less clear, but the first one the 'и' is stressed, second one 'а.'
The и should be stressed in all cases, I think, not sure why it would stress the a.
As someone previously mentioned, the accent is on the correct syllable when you listen to the whole sentence, but on the incorrect syllable when you listen to спасибо by itself. Hope they can get this fixed.