pss analysis fails in spectre

I'm simulating an LNA and pss fails on me. The simulator settings are default ones. I have heard for pss one has to change the tolerance settings. I don't know how and which setting. pls help. Here's the error:

Internal error found in spectre during periodic steady state analysis
`sweeppss-000_pss', during Sweep analysis `sweeppss'. Please run
`getSpectreFiles' or send the netlist, the spectre log file, the
behavioral model files, and any other information that can help
identify the problem to support@cadence.com.
Assertion failed in file `hopss.c' at line 1312.
Assertion failed.


Any help I can get is appreciated.