Piggybacking ethernet/phone on Cat5e?
I would check your connections to ensure you have left the green and orange pairs open for use with the Ethernet. Remember that the orange pair is separated by the blue pair, the wires are not side by side in the connector. Also, I would not include the extra two twisted pairs in the RJ45 connectors (blue and brown) you plug into the router. That way, the router has no way of trying to put data on those lines.

Both 10Base-T and 100Base-T use the same wiring topology, although 100Base-T needs the higher quality cable due to the increased transmission speeds. This should be the green pair (RJ45 pins 1 and 2) and the orange pair (RJ45 pins 3 and 6). The other two twisted pairs can be used for other data transmission, as long as the signal does not produce interference with the Ethernet.