Strange messages: HDLC Bad FCS (8) on Primary D-channel

Hello, everyone
I’m getting a lot of this messages on asterisk console:

chan_zap.c:8194 pri_dchannel: PRI got event: HDLC Bad FCS (8) on Primary D-channel of span 2

I’m just starting with asterisk. Could someone explain, please, what are those HDLC, FCS and (8).
As far as I understood from google this message basicly means that a wrong packet on an E1 line has been received. Is that bad? If so, where I should be looking for a problem (software, digium card, actual E1 line).
Thanks in advance

Hi

Is this often, or once in a while ? It points to a fault card or IRQ problem

Ian

Thanks a lot for your reply, Ian
The message appears at least once per minute. Sometimes more frequently.
I do have interrupt misses:
zttest
Best: 99.987793 – Worst: 99.975586 – Average: 99.976576
So, I guess I’ll try to give my card a higher IRQ. Hopefully the message goes away.
Thanks once again

Hi

You need to make up a loop back plug and see if you still get the error. Then compile and run the patern match utility to check the card.

Ian