I saw this with the new opa828, it would be interesting to try them

What do you mean by this? Of course, the sound is emitted by the iems from the applied voltage. Personally, I’m not going to modify it, because I think the problem is not in sensitive iems (it’s difficult to call Sony z5 sensitive). I don't hear a difference in noise when switching gain levels...

I probably need to return it too, but in my country, unfortunately, nothing can be returned without numerous courts. Xduoo support takes several months to respond. p.s. This is what they just answered Hi, If you use high-sensitivity in-ear earplugs, there is a slight white noise, which is...

There is an easy way to determine if there is no hiss or if you just can't hear it. "Spectroid" application for android. Just place your iems on the microphone. These are my results with 12ohm 115 db/mw, no sound, bluetooth (paired, amp is always on) and coaxial (amp off) inputs p.s. <1500hz are...

The output impedance is only 0.9, there are very few headphones that would be affected by it. Even on Andromeda the effect is quite small

Why not? This is a voltage divider and it does its job. Since this is only needed for small in-ear headphones, we won't experience any distortion from the amplifier at its maximum level. Amirm has a review of a similar device...

As I mentioned earlier, ifi iematch+ 3.5mm got rid of this problem, only now I set the volume on low gain to 40-50 instead of 10 without it. With 3.5mm BAL adapters this allows me to use the 4.4 output as well. 4.4 version of ifi iematch is not suitable, it has too high output impedance. p.s...

There is another strange behavior, a buzzing noise with some power supplies (mean well 12v, samsung 45w) which disappears as soon as you touch the xd05. There is no grounding in my house. I'm not an electronics engineer, but perhaps they connected the internal ground to the chassis. Maybe even...

I received it from China a month or two ago, the charging port LED is off in EXT mode

Yes, hissing. Indeed, I compared the sensitivity of our iems and found it strange. The only thing that affects the noise is the SE or BAL connection, in the latter case it is louder. I also hear it on Nicehck F1 pro (planar iem), Kiwi Quintet, Snowy A8 (115 db/mW 12ohm), no problems with...

This makes me wonder if my device is defective, the noise is disturbing in a quiet room even with a Sony XBA-Z5

I have hiss on both the stock opamps and the sparkos. XBA-Z5, kiwi quintet