Sony MZ-R70 Manuel

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Fix:  Some USB host controllers do not function within USB 
specification. Also Windows, in conjunction with other hardware in 
your system, may be consuming all the isochronous bandwidth of the 
USB bus. Both of these interfere with the data flowing to the Digital 
PCLink causing it to randomly insert track marks.
The main instaces where this occurs is if:
• USB frame rates are out of specification — isochronous data 
transfer (required for audio) is not possible via USB with a frame 
rate that is too fast or too slow.
• Controllers do not enumerate devices correctly — some controllers 
do not send USB resets at the appropriate times or may enumerate 
one part of a composite device.
• Corrupting audio data — some USB controllers introduce artifacts 
into sound data (i.e. CATC traces of USB data have shown non-zero 
vales in data that should be all zeros).
Make sure you are not running any other programs in the background 
when trying to record with the Digital PCLink — anything that 
causes a lot of hard disk access can effect the data flowing down the 
USB bus. Virus checking programs that continually run in the 
background are particular bad. Some drastically effect the 
isochronous data flow down the USB bus and starve the Digital 
PCLink of data. It is therefore important to disable all virus checking 
programs if you are getting multiple track marks. Also, make sure 
that you are running the most up to date drivers for your graphics 
cards and modems. If you are on a network, it is advisable to log off.
Note
If you are using a laptop or notebook computer, the data flowing to the Digital 
PCLink can be severely effected by the processing power management of the 
CPU. Ensure that in the System control panel your computer is set to Desktop. 
To verify this, go to Start, then Settings, then Control Panel. Click on 
System and go to the Performance tab. In Performance, click on File 
System
 and make sure your laptop is set to Desktop and not Server. Some 
laptops are not suitable for the decoding and recording of MP3 via USB due to 
the variable operating speed of their CPU and other power management 
features. Check with your laptop manufacturer to ensure that the USB 
environment on your system supports USB audio applications.