I have a XBee Radio on a device that we are trying to get to communicate with another XBee Radio 5' away (attached to PC). However, there is a lot of noise on the channel and the XBee is receiving a lot of gibberish only on that particular channel. My question: Is it possible to program the channel of the Xbee not attached to the computer using the one from the computer?? Will the noise make this impossible to do over wireless and will I need a hardwired connection to the second Xbee?
I think you may have misdiagnosed your problem. A noisy channel would result in delays of sending data, but won't result in random data. The coordinator typically checks all available channels and selects the one with the least noise when establishing a network.
It's more likely that another device joined the network and is sending data. Noise will limit the XBee modules' ability to send, but won't corrupt the data sent wirelessly.
Is it possible you have the XBee module in API mode when you're expecting Transparent Serial mode (also called AT mode)? In Transparent Serial, data on the module's serial port is passed directly to a destination device (specified in ATDH and ATDL).
If you're still interested in changing channels, you can control channel selection using ATSC (Scan Channels). It's a bitmask of channels the coordinator considers when establishing a network, and channels a router or end device will use when looking for a network to join. If you needed to avoid a specific channel, you could send a remote ATSC command removing the current channel from the bitmask, then possibly an ATNR (Network Reset) command. Then do the same on the coordinator so it creates a new network on a new channel.
If you've done everything correctly, the remote device will join the newly created network on the new channel. You might need to send an ATWR (Write) command to the remote device at that point, so it stores the new ATAC setting.