From time to time, FFXIV will constantly have the following error after anywhere from 1 to 5 minutes of gameplay:

An error has occurred on the game server. (30002)1345246648,26832369,5

In order to get back into the game, the whole client has to be shut off. The same continues to persist when logging back on.
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An error has occurred on the game server. (30002)1345246648,26832369,5
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Tried multiple times over multiple days. I've tried a combination of many things, including going from wireless to wired, using a Static IP, altering the MTU levels up and down (between 1480 and 1500), power-cycling my modem and router, etc. FFXIV is the ONLY online game/client/etc that is having problems over my connection. Otherwise, all else is very stable, connection tests averaging 10ms ping, 25 down, 2 up.

Date & Time: All of August thus far, most times (other than times way later in the day) CST
Frequency: Most always
PC Manufacturer & Model Number: Homebuilt Computer
OS: Windows 7 Professional x64
Graphics Card: NVIDIA GeForce GTS 250
ISP: RCN
Type of Internet Connection: Cable