Query about crc and error seconds

[#1]

Any one have info about what are acceptable levels of crc errors and errored seconds?
My router is currently reporting 21 CRC and 14 ES in a 4 hour period .
Is this normal for 4928 line rate with 50 dB attn (down) and 9.0 snr
The reason for my query is that I have recently changed to a new telephone and the errored seconds seem to have increased,
probably coincidence ?
Thanks,
Mike (edgeways)

[#2]

I have an attenuation of 30.5, and I'm running at 8128 without interleaving, so error correction is turned off. This means any errors are seen as CRC, and not FEC.
I get around 10 CRC per hour, about 8 ES per hour, and no SES. This is no problem whatsoever.
If your ES has increased, but the CRC hasn't, it just means that those CRC errors are more spread out in time, where on the old line, they were a little more concentrated.