D-Link DI-624 Wireless Router (WPA-PSK enabled)
Toshiba Satellite Laptop w/ WinXP Home (SP2)

I'm hoping someone can explain the following phenomenon wrt my wireless
setup. Personally, I'm stumped.

I own a D-Link DI-624 wireless router, configured w/ WPA-PSK. I just
purchased a new laptop (Toshiba Satellite) w/ Atheros built-in WiFi. Seems
to work fine except for one issue.

When listening to internet radio broadcasts, the audio stream periodically
drops out for 15-20 seconds every minute or so. The radio tuner usually
shows buffering during this period. I've used this wireless router w/
another PC desktop, but using WEP, and never experienced this problem
before.

For diagnostic purposes, I decided to run a continuous PING (ping -t
192.168.2.1) against the router to see exactly when this problem occurs, for
how long, etc. But here's the puzzling part. The PING *never* times out!
In fact, once I start the PING, the audio stream never drops out anymore
either! The audio stream works perfectly. As soon as I kill the PING, the
audio stream returns to periodically dropping out.

What the heck is going on here?! Why would running a continuous ping
against the router IP address result in keeping my audio stream running w/o
interruption? I'm pretty savvy about 802.11g wireless, but this phenomenon
has me baffled. Could it be related to WPA? Does this indicate another
problem that could be corrected w/o having to resort to keeping this
continuous PING running in the background?

TIA

Jim