LTB Audio Systems USB Pro 5.1 Surround Sound Headphone System - Manual (Page 9)

Case2--Install USB Multi Channel Dolby Digital sound technology driver
OS Support
Win98SE, WinME, Win2000, WinXP
System recommended use Intel P4 1GHz or AMD K7 above
At least 64 MB RAM (Win98SE) or 128MB RAM (WinME, Win2000 and
WinXP)
At least 80 MB hard disk space
Support direct sound 3D
Note : Windows OS has default USB driver support, but no support for HRTF
3D, EAX , Multi-channel sound effect and Dolby Digital sound DSP function.
Thus, if user wants to enjoy these experiences must install USB Multi
Channel sound audio driver.
Before users install USB Multi Channel sound audio driver, they must make
sure that USB Multi-media Sound Device has been connected to PC system
already.
If your PC system has more than one USB port, please remember
which one is connected for install, and next time when you plug the USB
Multi-media Sound Device to PC, you have to plug in the same port to initialize
the USB Multi Channel driver.
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