I've never heard a hiss in my friends, and he confirms that he has never heard a hiss.
The thing you mention about the chip is speculation correct? We do not know a Tenor chip is implemented in the X1Pro do we??
I hear what your saying and I've also read a bunch or informal reviews, heard one (X1) firsthand and this is the first mention of either of those issues.
I'm confident this is a great oppurtunity.
ecleinit all depends on how sensitive your headphones are, there are some IEM's out there that can make even the blackest headphone amps display hiss, power conditioning helps greatly as well.
Yea pure speculation regarding the USB receiver, its a good guess though, the T1 uses a TE7022L, and the next logical evolution is a TE8802L.
The Yulong D200, the DA8's little brother looks promising, XMOS receiver, 32ohm:1W etc, its bound to be listed here any moment.
Edit: looks like it just uses a TE7022, same as the T1, ah well.