Problems with TDM configration-PRI configuration

Hello,

we have a problem with configuring a PRI on our 3900 SBC. We use standard configuration:

tdm-config

state enabled

logging enabled

line-mode e1

tone-zone es

calling-Pres allowed_not_screened

caller-ID no

tdm-profile

name Prosegur

signalling pri_cpe

switch-type euroisdn

b-channel 1-15,17-31

d-channel 16

span-number 1

route-group 0

line-build-out 0

framing-value ccs

coding-value hdb3

crc4-checking enabled

timing-source 1

rx-gain 0.0

tx-gain 0.0

echo-cancellation enabled

overlap-dial no

incoming-pattern _X.

called_type_of_number unknown

calling_type_of_number unknown

but we get a lot of crc errors:

Tdm Command Output

Description Alarms IRQ bpviol CRC Fra Codi Options LBO

WCTE43X (PCI) Card 0 Span 1 OK 0 0 189763 CCS HDB3 CRC4 0 db (CSU)/0-133 feet (DSX-1)