Bluetooth works perfectly with the XTZ Divine I'm reviewing at the moment. Also with the SB Roar2, and when connected to my car. Faultless really. Not sure if it might be just your unit? Can you try any other Bluetooth audio devices?
Headphone Reviews and Discussion - Head-Fi.org
Brooko
Hitec
The item is on the way back. I hope to see someone else's experience with the X7's Bluetooth connection. I really hope that it was just my unit, and not a thousand plus units.
Stachu P
Hey Hitec!
Happy to come across your review, for I have EXACTLY same issue with my unit! Currently I have two different headsets @ bluetooth - Sony MDR-1ABT and Monster BH-940 Purity Pro - and same "frying bacon", as you accurately described it, happens there. Also same range of feq, i.e. lower to middle high, usually at instrumentally dense fragments. It does not affect every sing, but it is quite annoying as the bluetooth support of the X7 was a deal breaker for me. Also, at times (quite often I regret to say) I noticed that the music across the frequency range is not as clean at all, I agree sounds cheap at best. Unacceptable for this class of DAP... Of course, when change to cable it is whole different world... Of course, when I use the headphones on my PC or mobile, it is just perfect, so....
Firmware updates do not help (yet..). I read somewhere it may be related to bluetooth connectivity implementation in Android 4.4.X version. Hopefully FiiO will address it at some point, would hate to return it for this reason, thought quite crucial for me. I also hope this is just my nit's fault, but well, are at least two of us...
Happy to come across your review, for I have EXACTLY same issue with my unit! Currently I have two different headsets @ bluetooth - Sony MDR-1ABT and Monster BH-940 Purity Pro - and same "frying bacon", as you accurately described it, happens there. Also same range of feq, i.e. lower to middle high, usually at instrumentally dense fragments. It does not affect every sing, but it is quite annoying as the bluetooth support of the X7 was a deal breaker for me. Also, at times (quite often I regret to say) I noticed that the music across the frequency range is not as clean at all, I agree sounds cheap at best. Unacceptable for this class of DAP... Of course, when change to cable it is whole different world... Of course, when I use the headphones on my PC or mobile, it is just perfect, so....
Firmware updates do not help (yet..). I read somewhere it may be related to bluetooth connectivity implementation in Android 4.4.X version. Hopefully FiiO will address it at some point, would hate to return it for this reason, thought quite crucial for me. I also hope this is just my nit's fault, but well, are at least two of us...
Hitec
Yea, I just figured, if my PC's bluetooth does not have a problem sending audio to my Parrot bluetooth headset, then the X7's bluetooth should not have a problem sending audio to my Parrot bluetooth headset. At first, I was thinking that it could just be that the X7 does not like the Parrot, but I see that it does not like the headset that you have either. Now the common point is the X7. I also moved around to different places in the house to ensure there was no interference in the air - didn't change anything. I really enjoyed the X7, but I use bluetooth as well, and since it is not cutting the cake, I returned the unit. Of course we can't go long without our sounds, so Onkyo's DP-X1 will be in to replace it next week, and probably since I'm one of the early adopters of that DP-X1, I'll experience issues with that unit. Hey, that's why we enjoy this music/hobby 
sledgeharvy
@Hitec I have to update my review of the iBasso DX80 with my ramble, but long story short.
I bought all sorts of headphones getting incremental SQ. Howver no matter how much I spent, I was always left with a sense of congestion that would not go away.
So I was left to realize, it was my source. After I upgraded to a headphone amp, I started getting better results. Finally, I moved on to a DAP first the Fiio X5ii, then down to the X3ii, and now the iBasso DX80... And now I'm happy, the congestion is gone, the itch is finally scratched.. However now, I am forced to deal with other issues.. (Issues of non-polished OS's.) So what can I do? I finally have the sound I want but a faced with players and I mean all of them, that have issues plaguing their OS's.. But I gues at the end of the day, that's why this is a hobby.. Just have to keep buying more stuff.
By the way, I forgot how to listen to "Music". I noticed that yesterday.. I was more fascinated with how clear yet bassy it all was. Instead of listening to the music for what it was and how the music let me feel. Lol...
I bought all sorts of headphones getting incremental SQ. Howver no matter how much I spent, I was always left with a sense of congestion that would not go away.
So I was left to realize, it was my source. After I upgraded to a headphone amp, I started getting better results. Finally, I moved on to a DAP first the Fiio X5ii, then down to the X3ii, and now the iBasso DX80... And now I'm happy, the congestion is gone, the itch is finally scratched.. However now, I am forced to deal with other issues.. (Issues of non-polished OS's.) So what can I do? I finally have the sound I want but a faced with players and I mean all of them, that have issues plaguing their OS's.. But I gues at the end of the day, that's why this is a hobby.. Just have to keep buying more stuff.
By the way, I forgot how to listen to "Music". I noticed that yesterday.. I was more fascinated with how clear yet bassy it all was. Instead of listening to the music for what it was and how the music let me feel. Lol...
