We have a branch office connected by a point-to-point T-1. The branch office router will accumulate CRC and Frame errors and various times during the day. It is at this time that users report issues from the site. I have had the SP test and of course they say the circuit it clean. Of course while testing is being done the issue is probably not happening. I have ran my own loopback test on the equipment with no errors. The T-1 controller gets line and path code violations. We have verified framing and linecode settings are good. The other end of the circuit (headquarters)is complete clean of any errors. Thanks in advance for advice.