Almost the same in pronounciation, both sound like /hi/, as for me, I don't tell the difference.:) \^o^/

The sounds of 희 and 의 are the same. But the sound of 의 and 이 are different. https://forum.wordreference.com/threads/pronunciation-of-의.2794822/

technically the sound should be different but if you listen carefully to people in everyday conversation you would notice they almost sound the same sometimes, particularly when they speak in a haste.