Struggling to hear the difference between the sibilants in Basque

I record myself daily to check my pronunciation, but I’m struggling to distinguish between the 's', 'z', and 'x' sounds when listening to native media. I feel like I'm hitting a hard listening plateau where everything just sounds like static. Since I only have 20 minutes a day to dedicate, are there specific exercises or minimal pairs I should focus on so I don't sound like a tourist when I visit Euskadi?