If the EA6300 router is still working except for the wireless range, try to consider moving the EA6300 like they suggested and/or make use of a wireless extender to extend the wireless range of the router. Try the inSSIDer to scan your wireless network and check if your router is using crowded Channels. No need to set MAC Filter. Just make sure it is not Enabled if not needed. But if you are open to a model upgrade, go for it.
About the iPod, now that you mentioned it being blocked by Parental Controls, try removing it from the block schedule temporarily and check if it is still not able to access the internet.