hey i found this thread through google while looking up a very similar topic

as of today 11/25 i received my m40x adapter the same one from the amazon link and I ordered it brand new for the current $29.95 price and not the warehouse discounted ones.

i didn't really have many expectations as it is bluetooth but as the box long cables are very inconvenient I gave it a try and my thoughts are:

• the frequencies are all messed up, the MIDS ESPECIALLY, the vocals sound so hollow and distant.
• the connector between the adapter and the headphones is loose, there nothing hold it together, it definitely fits and connect but i feel like if i bump it or move suddenly it might just fall off
• i listened to type of music to test: metalcore - spirit breaker by august burn red (full volume) the beginning orchestral violin + cello are perfect but still strangely hollow for it being at full volume and when the vocals and guitar kick in its so bad the treble is so high everything is distorted and it just hurts to listen
• the 2nd type is indie folk/pop - tom walker - and its either you can hear the vocals with distant soft acoustic or you only hear the acoustic with the vocals being so soft.

maybe my particular pair is bad, but im requesting a replacement and sending it back. if this 2nd one is no good, i'll let you know.

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