Strange CANBus Issue

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Hi Everyone,
I'm new to the AVR world, and I am trying to troubleshoot an odd CANBus issue that I'm encountering while using an XMEGA32C and MCP25625 Chips.
I am currently pulling the 16MHz crystal to 32MHz for most of my timing, although I'm using a period of 1 to bring the clock back to 16MHz for the CAN stuff.
I have a board that takes messages from one bus, and re-transmits them on another bus. This works completely fine at 1mb, 500k and 250k currently.

I am now trying to set the baud of the MCP chips to 83.333k, which seems to work okay when I'm testing on the bench using 2x PCAN-USB dongles as the endpoints, however when using the device in a vehicle, I am not seeing any traffic being passed from one bus to the other.
Oddly, I am able to see a couple of messages come through (at a very slow rate) when I transmit messages back in the other direction (PCAN>Vehicle) using a PCAN on one side of the device and the vehicle on the other.

I have tried to research the issue, and I have seen that some people have encountered something similar and that using a cheap MCP board with an 8MHz crystal seemed to work.
I'm going to try and slow the clock to 8MHz tomorrow to see if that works, but I'm posting here in the meantime hoping that someone that understands this better than me can enlighten me.
I'm confident that its some odd timing issue with what I'm doing, and if I need to post some code I'm happy to.