You may have run into Bug 9104898: ORION FAILS WITH ORA-27061: WAITING FOR ASYNC I/OS FAILED
BUG 9104898 mentions that version 126.96.36.199 is working
You did not mention which orion version you are running. The orion tool is part of the Oracle Database 11gR2 installation. I suggest to try the latest version that ship with the Database installation.