SQL 2008 R2 - Odd timeout issues
Try looking at a couple of things to help determine if you are having issues with the network.
Wait Stats

ASYNC_NETWORK_IO

On The Server

Network Interface:Output queue length
Redirector:Network error/sec

This should always be zero


TCPv4:Segments retransmitted/sec &amp; TCPv6:Segment retransmitted/sec

When divided over the total number of segments should not be more than 3%.