I've got a site that had a RB1200 running 6.35.2 that was failing, so I replaced it with a CCR1009-8G-1S-1S+. I'm seeing Rx FCS Errors at a rate of around 1 an hour - I was not seeing this on the RB1200. The CCR is also running 6.35.2. I tried enabling flow control to see if that made any difference, but it did not appear to fix the situation. Any ideas what could be causing this?

The error counters on mine are still all at zero after a month of uptime.
But at that rate I would not worry about it... FCS is apparently doing what it should do.

You can try to use shielded cables.

You can try to use shielded cables.

I already have shielded cables at this site.

same problem here as well, 596 FCS Errors in 30 days
is not sooo much, but is not ok !!
no errors on RB1100 before

name="ether11" driver-rx-byte=5 347 481 269 413
driver-rx-packet=8 213 181 544 driver-tx-byte=2 765 326 209 750
driver-tx-packet=7 177 303 996 rx-bytes=5 380 334 039 817
rx-packet=8 213 182 141 rx-too-short=0 rx-64=285 898 590
rx-65-127=3 088 117 979 rx-128-255=1 359 824 479 rx-256-511=263 287 870
rx-512-1023=96 371 313 rx-1024-1518=918 061 523 rx-1519-max=2 201 620 387
rx-too-long=0 rx-broadcast=175 127 rx-pause=0 rx-multicast=1 472 634
rx-fcs-error=596 rx-align-error=0 rx-overflow=0 rx-length-error=0
rx-code-error=137 rx-jabber=0 rx-ip-header-checksum-error=0
rx-tcp-checksum-error=0 rx-udp-checksum-error=0
tx-bytes=2 795 559 380 866 tx-packet=7 177 303 996 tx-64=751 223 219
tx-65-127=3 403 332 415 tx-128-255=1 248 555 192 tx-256-511=308 521 507
tx-512-1023=82 338 869 tx-1024-1518=523 259 399 tx-1519-max=860 073 395
tx-broadcast=3 342 012 tx-pause=0 tx-multicast=7 615 027 tx-underrun=0
tx-excessive-collision=0 tx-multiple-collision=0 tx-single-collision=0
tx-deferred=0 tx-late-collision=0 tx-fcs-error=0 tx-carrier-sense-error=0

What is at the other end? I have a CCR1009-8G-1S-1S+ connected to a HP/Procurve gigabit switch using
a couple of 1 meter CAT6 patchcords and the error counters on both sides remain at zero.

we have about 60m Cable and a SUB10 Gigbit microwave unit at the end, no errors there....