Often, it feels that the language will play tricks on you, especially when you're starting to get complacent (about having formulated some clever "rule" or mnemonic).
The general rule (note the use of "general") is one element of the character is the radical -- tells you what category it is: hand-related, water-related, etc.; the other is the phonetic -- tells you what the sound is (not the tone). Well, not always.
This is the example I always use in my teaching (I'm not bringing the tones in, as same phonetic doesn't always = same tone):
The reading for 番 is "fan", so it should follow that 翻 should be "fan" as well. Correct.
The reading for 潘 should be "fan" too, since it has the same phonetic 番. Wrong. It's Pan (a surname). OK, even if they have different initial consonants ("f" / "p"), at least they have the same vowel sound ("an").
播: (i) first guess: reading should be "fan". Nope. (ii) "pan" then, given the 潘 experience above. Nope. What's the reading? "bo" --> totally different initial consonant from the others, totally different vowel.
In case you're thinking it's because the simplification process has ended up making them all have the same phonetic: no, the characters are the same images in the traditional script.
Rule / Lesson: Do not take the Chinese language for granted. Never be complacent! (As I say to my poor students who feel constantly wrong-footed.)