Got error 134 when reading table

I am running
Red Hat Linux 3.2.3-20
5.0.18-standard
with the data directory on a RAID5 filesystem ext3
data is inserted into the CDRS table @ 100000 record/hour
and then moved to RATEDCDR

I keep on getting these errors:
060204 12:56:50 [ERROR] Got error 134 when reading table './cdrs/CDRS'
060204 12:59:12 [ERROR] /usr/local/mysql/bin/mysqld: Incorrect key file
for table './cdrs/RATEDCDR.MYI'; try to repair it

I have tried to use myisamchk and even created a new table and the
system runs fine for a while and then the same error.

Any suggestions?