If you create a network of two brokers, A and B, one publisher publishing to A, and n (where n is > 1) receivers with selectors, each receiver recieves n messages for every 1 message sent. The key here is to have a selector. It would appear that the conduitSubscriptions flag does not work when using selectors. The conduit does not properly reconcile consumers if they have selectors. A suggested soltuion would be that ather than process each selector independantly, each selector should be or'ed together and if any selector results in true then a single message should be sent to the other broker.
In doing research, it would appear that this problem was introduced with bug fix
AMQ-810. Another user reported it via email back to the assignee of AMQ-810 and a short dialog transpired. See http://firstname.lastname@example.org/msg05198.html.