OS cannot edit unicode tag correctly

That is strange.
I too use v2.3 UTF-16 tags, though through MP3tag, and they look fine.

tag.JPG

At the top of the tab from your second screenshot, try to switch from v2.3 to v2.4 and see if it makes any difference. Alternatively, try another tagging software.
 

My Computer

Computer type
Laptop
Computer Manufacturer/Model Number
Custom
OS
Windows 7 Home Premium x64
CPU
Intel Core i5 2500K
Motherboard
MSI MS-7750
Memory
8GB DDR3
Graphics Card(s)
nVidia GeForce GTX650 Ti BOOST
Sound Card
Realtek
Monitor(s) Displays
21' Philips
Screen Resolution
Full HD
Hard Drives
1TB
PSU
500W
Thanks, but the tagging software works properly since yesterday with same settings, I dont know why...:sarc:
 

My Computer

OS
Windows 7 VL (64-bit)
Internet Speed
PCCW Global IMS Ultraline@500Mbps (FTTH)
I've had a similar problem while testing a couple of MP3 files. AAC, as you can see, isn't affected by it at all xD
 

My Computer

Computer type
Laptop
Computer Manufacturer/Model Number
Custom
OS
Windows 7 Home Premium x64
CPU
Intel Core i5 2500K
Motherboard
MSI MS-7750
Memory
8GB DDR3
Graphics Card(s)
nVidia GeForce GTX650 Ti BOOST
Sound Card
Realtek
Monitor(s) Displays
21' Philips
Screen Resolution
Full HD
Hard Drives
1TB
PSU
500W
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