Haydn,
Since this community doesn't provide technical support and is not staffed with technical support experts, I recommend you also post this to the Cisco Support Community (Cisco Support Community) where our Cisco technical support experts provide assistance. Another option is to open a ticket with the Cisco Technical Assistance Center (www.cisco.com/go/support) to get expert debugging assistance.
I hope this helps. Thank you for participating in the community.
Kelli Glass
Moderator for Cisco Customer Communities