I have the same question. "I am eating if you drink" sounds natural as a sort of challenge to the other person not to drink. "I am eating if you are drinking" is also natural, perhaps two people sitting down together to wait for a few minutes and deciding what to do while they wait. "I eat if you drink" isn't something I can imagine a native English speaker saying.
True, but having an "if" in the present continuous tense doesn't always make sense. "I am eating WHILE you are drinking" or "I am eating BECAUSE you are drinking" are acceptable, but if you're talking to someone, you can see whether or not they're drinking, so it wouldn't be an "if."
"I will eat if you are drinking" would make sense though, because it is obviously referring to the future.
Two men enter a bar. The first wants to know if his companion is going to get food. "Are you eating?" he asks. The second man is hungry, but he knows his friend has already eaten and doesn't want them to stop there on his account alone, but he thinks maybe his friend would be getting a drink anyway. Thus, he replies: "I'm eating if you're drinking." The first man laughs and orders a round. The second, taking the cue, checks the menu for food.
I'd bet it's a buffering issue. You can load up a module and turn off your internet, then finish the module (I use this for the commute to work)- some times it will even have a few more in memory. I'd wager that the audio takes up a bunch more space, so sometimes your device will prioritise the text if there's a network interruption.