1. 기분 탓입니다 2. 한국어에서 첫 자음은 다소 거칠게 발음됩니다. 특히 'ㅏ' 모음과 조합되는 경우 더 강하게 발음됩니다.

It doesn't pronouns that way. It's wrong. The right way is more like Jin zza. Let your front-top part of tongue slightly touch the backside of the upper-teeth when you pronouns 자. Then you probably get the sound.be careful, not CA or ChA, zzza, imaging lots of Z before A. 잡채, you just need to pronouns literally. Why you hear it that way, I guess is that, there are more air going out of the mouth when trying to pronouns it quickly, it would probably change the sound to that way.