>>105982203
>>105982227
>>105982266
I'm guessing the culprit here is a bad seal. Try different tips.

Sometimes you can have an "okay" seal that keeps some of the bass but still lets out the lowest frequencies. Generally the longer tips help in this situation.

With bullet IEMs I generally need smaller tips to get the right seal, for over-ear IEMs I need longer tips. The KZ ATE and Blon BL05 need really long tips.