I have a queston regarding the pronunciation of часо́в and часа́.
Why in Pimsleur I hear it as чисо́в and чиса́?
Even in google translate it seems to change from часа́ when the word is alone by itself, but it changes to чиса́ when I add the numbers.
Other resources like https://www.russianforfree.com/phrasebook-tell-time.php it always sounds like часа́.

So what am I missing? what is going on?