I get buffer underruns when using CD Architect.

A buffer underrun is caused when data cannot be transferred to the CD recorder fast enough. Various steps can be taken if buffer underruns are a consistent problem. These are covered in great detail in the Optimizing CD Architect section of the manual and online help file.

Some steps you can take to avoid buffer underruns:

1. Defragment your hard drive.
To make sure data can be transferred as fast as possible to and from the hard drive, you should defragment it often. This will reduce the potential for buffer underruns when writing the CD. You should probably do a “files only” defragmentation, each time before you burn a CD. If you are going to create an image file, you may want to defragment the free space on the drive beforehand.

2. Turn off Auto Insert Notification (AutoPlay).
Auto insert notification allows Windows to know that a CD has been inserted into a device. It involves the periodic polling of devices on the system. Under normal use, it is usually benign, but when burning a CD the resources it uses can create a big problem. It should be turned off for any CD-ROM or CD-R device on the system.

CD Architect will notify you prior to a write if AutoPlay is enabled for one or more drives that are on, or were on, the system. To disable these warning messages you can uncheck the Warn if auto insert notification (AutoPlay) is enabled option on the General page of Preferences.

To disable auto insert notification:

a. Windows 95 To turn off auto insert notification on Windows 95 for a specific drive, open the Properties for My Computer. Select the Device Manager page and expand the CD-ROM entry. Select the drive that you want to disable auto insert notification for and click Properties. Go to the Settings page and uncheck the Auto Insert Notification option.
Auto insert notification can be disabled for all drives that are on, or were on, the system by choosing the option on the General page of Preferences to disable AutoPlay for all CD drives.

b. Windows NT Windows NT does not have the ability to disable auto insert notification for specific drives. There is also no standard dialog for configuring this option. Because of this, CD Architect contains an option on the General page of Preferences to disable AutoPlay for all CD drives. It is strongly recommended that you disable AutoPlay on Windows NT if you are reading or writing CDs with CD Architect.

3. Use the right CD Media
There are two basic types of blank CD media out there today: cyanine (green-colored front) and pthalocyanine (gold-colored front). The manufacturer of your CD-Recorder has most likely tuned the recorder to operate optimally with a certain type of media. You should use the media that your manufacturer recommends. Regardless of the hype that you hear about the pros and cons of each type, your manufacturer knows what works best in their recorder – use it!

4. Close Background Programs
Turn them off! This not only means obvious applications like Microsoft Word, but also the not so obvious things such as Microsoft Find Fast, System Agent and Screen Savers. Anything that could be walking around your system while you are trying to write a CD can cause buffer underruns.

5. Create Image Files
CD Architect writes data directly from the hard drive to the CD. While it is doing this it is also calculating all of the volume envelopes, crossfades and mixes in real-time. This might be a problem depending on how fast your computer is. If you have a lot of these real-time functions in your CD project you might consider creating an image file before you burn. An image file is essentially a .WAV file that is rendered with all of the mixes, fades, etc. and the PQ information embedded inside. Creating this file and then burning it will greatly reduce the strain on your computer and reduce the risk of buffer underruns.

To create an image file:

a. Choose Save As from the File menu.
b. Change Save as type to CD Image.
c. Name the image file, and press OK.

To open an image file:

a. Choose Open from the File menu.
b. Change Files of type to CD Image.
c. Choose the image file you wish to open, and press OK.

6. Get off of the Network
If your computer is connected to a Local Area Network, disconnect it while you burn your CD. The increased overhead associated with monitoring network connections can sometimes cause buffer underruns. As well, if anybody on the network accesses your computer during a burn, you are guaranteed an instant coaster.

Another network issue has to do with using TCP/IP through a LAN connection. This does not apply if you only have TCP/IP setup using a dial-up adapter. Under Control Panel/Network, double-click the entry that reads TCP/IP followed by the name of your network card and then choose the IP Address tab.

If you are using TCP/IP on a LAN, you should only check ‘Obtain an IP address automatically’ if your network has a DHCP server. This server automatically assigns IP addresses to client machines. If you have this option checked but you do not have a DHCP server on the network, Windows will freeze for a few seconds periodically as it attempts to obtain an IP address. This will definitely cause buffer underruns if it happens during a burn.

There are many network issues not addressed here, so the best solution is not to use a networked machine for CD burning. If you must use a networked machine for CD burning, the best thing to do is physically disconnect your network connector on the back of the machine and then start up Windows. This guarantees that you will not be on the network. However, the DHCP problem described above may still exist even if you physically disconnect yourself from your network.

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