Sounds like you may have Activity Trace turned on.
Two things to check here.
- Issue the following MQSC command
DISPLAY QMGR ACTVTRC
If it says ON, then ALTER the QMGR to turn it OFF.
- Check the contents of the mqat.ini file in your queue manager directory. The settings in that file can over-ride the other attribute.
If you want to see what the contents of the queue say, you can use the sample amqsact to format out the activity trace that has been collected.
Cheers,
Morag