[SAC-HELP] error on spectrogram

[jenni wang]

I am using SAC version 101.4 on Ubuntu latest version. I was running the
SPECTROGRAM command when I came to the error:
Window size: 200  Overlap: 100  FFT size: 512
Instability detected in spectral                         estimator,
increasing ridge regression                         factor to 1.00000e-04.
Instability detected in spectral                         estimator,
increasing ridge regression                         factor to 1.00000e-03.
Instability detected in spectral                         estimator,
increasing ridge regression                         factor to 1.00000e-02.
Instability detected in spectral                         estimator,
increasing ridge regression                         factor to 1.00000e-01.
Error:  Could not stabilize high res. spectrogram

Would anyone please help me to solve the problem?

I check that there are several emails in the mailist that asked the similar
question but unfortunately I can't find the answer there.

I appreciate any help and suggestion.
Thank you in advance.

Regards,
Jenni
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