I am completely new to Korean, so this question might just be the result of me hearing sounds incorrectly.
I watched FluentForever’s videos on pronunciation and spelling rules to get a first approach to reading Korean. Starting at around 6:20 they explain how several spelling rules can lay on top of another. (https://www.youtube.com/watch?v=BcvADOTNVzM)
They then explain why 꽃아니요 is pronounced [ko.da.ni.jo] rather than [kot]+[a.ni.jo]. However, while studying I came across this sentence: 네, 맞아요. Especially troubling for me is the pronunciation of 맞아요, as it doesn’t sound like [ma.da.jo] but rather like [ma.dza.jo] to me. (https://de.forvo.com/search/%EB%A7%9E%EC%95%84%EC%9A%94/) .
I found out that 맞아요 is a conjugated form of 맞다. I just don’t know if that has anything to do with this issue. I am aware of the fact that we're dealing with two different consonants here, however, according to the rules in the linked video, both should be turned into an unrealised [t] sound and then, due to another rule be turned into [d].
So my question is, why does ㅈ sound like a [dz] in 맞아요, but ㅊ like a [d] in 꽃아니요.