ISDN Errors -bristuffed-

Asterisk Asterisk Support
1

My pbx keeps displaying these errors:

chan_zap.c:7545 zt_pri_error: PRI: !! Got S-frame while link down
and
!! Unknown IE 26 (cs6, Unknown Information Element)

Configuration:

asterisk 1.09 wit bristuff and 1 isdn zaphfc 1 BRI

Any clues?

Thanks