Seem to effect version 2.1, 2.2 and 3.0. Also it seems disabling Bluetooth on your Ipod can improve performance.
Good find BTW.
More info:
The Beacon Interval value indicates the frequency interval of the beacon. A beacon is a packet broadcast by the router to synchronize the wireless network. 50 is recommended in poor reception.
What is a Beacon?
A typical beacon frame is approximately fifty bytes long, with about half of that being a common frame header and cyclic redundancy checking (CRC) field. As with other frames, the header includes source and destination MAC addresses as well as other information regarding the communications process. The destination address is always set to all ones, which is the broadcast Medium Access Control (MAC) address. This forces all other stations on the applicable channel to receive and process each beacon frame. The CRC field provides error detection capability.