problem writing CDs

[hubert.fauque@wanadoo.fr]

I used to write CDs with cdrecord without problem;
but now almost every time I try to write a CD
it ends with a SCSI error:

cdrecord: Input/output error. close track/session: scsi sendcmd: retryable error
CDB:  5B 00 02 00 00 00 00 00 00 00
status: 0x2 (CHECK CONDITION)
Sense Bytes: F0 00 05 00 00 00 00 28 00 07 F3 17 2C 04 00 00
Sense Key: 0x5 Illegal Request, Segment 0
Sense Code: 0x2C Qual 0x04 (current program area is empty) Fru 0x0
Sense flags: Blk 0 (valid) 
cmd finished after 0.016s timeout 480s

I haven't changed anything to the hardware; 
I am using potato on a Celeron 333;
do you think it's a hardware error? 

thanks for helping

Hubert