I am using the Duolingo Hebrew deck on Memrise Decks on iOS Safari on my iPhone XS.
When I start a lesson the first word has no audio. It happens all the time. The next word and following work fine.
This is most annoying in Learn New Words because I don’t see a way to replay the audio. I just don’t get to hear the word and have to move on to the next one. For the Listening Skills it is annoying but I can tap on the speaker icon to hear it.