Yup, always make sure to use OTG cables (allows for data transfer) with dongles. Some of us still have those micro-USB phones/devices and so we can forget that it's a requirement and another point of incompatibility if it's somehow not implemented properly.

This thread link talks about the Qudelix 5K, AptX Adaptive dongles, and specifically Apple devices: https://www.reddit.com/r/headphones/comments/zc1znn/qudelix_5k_arent_these_issues_a_big_issue/iyuh35j/

Extra Qudelix stuff, like Bluetooth capabilities, et cetera: https://www.reddit.com/r/headphones/comments/11832uu/qudelix5k_hidden_gem/j9hq4fd/

See here for more info about Qudelix 5K, parametric EQ, squig.link comparison graphs, AutoEQ, et cetera: https://www.reddit.com/r/headphones/comments/109meb5/eq/j40cy1n/ and https://www.reddit.com/r/headphones/comments/11ahxu1/just_picked_up_the_dt990s_250ohm_for_my_pc_sound/j9s5sht/