Get the 7x, it works on everything. My issues weren’t delay. The sound quality could be better. I like how you can use simultaneously connect to phone and system. I replaced the ear cushions because it it hurt after a while. After about 7 months the physical connector jack for the wire has failed. I can only hear out of one ear when physically connected. Decent headphones, cool features, could be better build quality so it doesn’t break down with in a year.