Boot Loader Menu appearing in S2C serial data

So I have four Zigbee S2C’s and have been having some strange trouble with them. I was working with an Arduino Uno and using AltSoftSerial, and with a simple code setup that just dumps serial data back and forth, the Boot Loader menu seems to be getting pulled up, and I have no idea why.

.B-Bypass
.F-Update App
.T-Timeout
.V-BL Ver.
.A-App Ver.
.R-Reset

This will appear in the serial data, and I believe it’s causing my problems with the serial data.

That’s bootloader menu of programmable XBee (MCU+XBee). Press “B” to bypass MCU and then you will have direct access to XBee’s radio.