I have just uploaded an important update to apt-p2p that is highly recommended for all users.
At some point over the last 48 hours bittorrent nodes have started to infiltrate the apt-p2p DHT (you may have noticed many ValueError tracebacks in your log file). The (mainline) bittorrent DHT is very similar in protocol to apt-p2p, and so the nodes are able to partially communicate and pollute each others routing table. I didn't think this would ever happen, as there wouldn't seem to be a reason for them to ever come into contact, but somehow it did.
I've made some minor changes that exploit the differences between the two protocols to exclude bittorrent nodes from the apt-p2p routing table, and to drop any requests from bittorrent nodes (which should prevent apt-p2p nodes from polluting the bittorrent DHT). However, it is very important that all users upgrade to this new version to prevent any further mixing of the DHTs.