Can you provide your VTune Amplifier XE results with debug info? You may make the forum thread private for it.
1. Set environment variable TPSS_COLLECTOR_TPSSTOOL_DEBUG to value "t":
2. Run your collection
3. Archive the result directory and attach to the thread.
We'll take a look at yourcollection. Also please provide name of your extension and some function names from it to look for.