underrun occurs when the buffer of the CD writer becomes empty.
The "buffer" holds all the data before they are written
to the disc. If buffer underrun happens, then the writer has no
data to write. The CD-R writer can only stop writing to the disc
and the mastering software will come up with an error.
How to solve buffer underruns problem?
Buffer underruns are caused by your system not transferring data
to the CD-R writer fast enough. If you are using a CD-R writer
connected to a computer not purposely configured for CD-R writing,
then buffer underruns can occur for a number of different reasons:
If your HDD is fragmented, data cannot be taken from it quick
device is to slow. Copying "on the fly" from a slow
CD-ROM, a zip drive, a floppy drive, or other slow devices is
devices do not transfer data in a constant stream.
If you have such a source device, sooner or later, it will drop
devices do not sync properly. If the CD Writer
starts to write before the CD-ROM or HDD has Spun up, you may
get a buffer underrun straight away.
Some IDE Interfaces are too slow to cope with writing "on the
of the above hardware problems can be eliminated by creating an
image of the CD before writing. You should also defragment your
HDD at regular intervals, preferrable about once a week.
you are experiencing buffer
underruns but you believe your hardware is alright, then make
sure all of the below are disabled.
any program that may activate on its own. This can include Screensavers,
Fax and E-mail systems, anti virus software, screen savers,
schedulers, and TSR software.
off any abnormal sounds.
off any backgrounds or animated icon which may be loaded up.
before you start recording, check to see what you have running
on your system. This can be done in Windows 95 and Windows 98
by pressing "Alt, Ctrl, and delete" at the same time
once. You will be given a list of programs running on your system.
There are only a few programs on this list which need to be running
to write the CD. Close down the programs that you do not need
for CD-R writing.
If you still experience buffer underruns problem after checking
all the above, try the following to improve the situation:
Access the Performance tab of the System properties window under
"system" in the control panel. Click on "File System",
change the "Typical role of this computer:" to Network server.
Underneath this, change the "Read-ahead optimization:" to None.
click on the CD-ROM tab, change the "Supplemental cache size:"
to Small and the "Optimize access pattern for:" No read-ahead.
you are still getting problems, change your "Virtual Memory"
settings. By clicking on the "Virtual Memory" button
you will be given a choice of either "Let Windows manage my
virtual memory settings" (default) or "Let me specify my own
virtual memory settings". If you change the option to the latter,
you can then change your minimum and maximum settings. Depending
on how much RAM you have, and what type of programs you run
on your PC, your settings will change. You should set the minimum
and the maximum to the same value. As a rough guide, with 64Mb
of RAM and for those who uses their computer primarily for Internet
exploring and word processing, the virtual memory could be set
to min=max=40. If you have problems running certain programs
with these settings, increase both the minimum and the maximum
the computer is connected to a network, you should log off the
network. This is because another computer may be accessing your
HDD while you are writing a CD. This may result in a Buffer
the BIOS to disable all memory shadowing, except video and system
There is a new
technology call "BurnProof"
used in some recorders that aims to eliminate buffer under run problems.