The PCLXL stream is probably corrupt, since 0x1b is not a valid value for an Operator tag (or any other type of PCLXL tag, as far as I am aware). Or it just might be that the stream is prototcol version 3, and contains embedded PCL, but your printer only supports an earlier version of the protocol?
You need to find out a bit more about just what your driver is generating before after the error position. To do this, choose 'print to file' instead of direct to the device.
Then you'll need to perform some analysis on the resultant file, first searching for the 8369'th operator in sequence.
You'll need some sort of analysis tool to help with this - HP provide a PCLXL assembler/disassembler tool (JetASM) via their developer association - you can join as an affiliate (free) via hpdevelopersolutions.com