PBDE surrogate factor/ calculation issues


I have successfully used surrogate calculations for masshunter with other methods (recoveries of surrogates against internal standards).

This method I created seems to be glitching every so oftten. The standards appear to form a nice calibration using average of response factors, include origin, no weight. Sometimes when I calculate samples though, it multiplies by 2 for some reason leaving my surrogates 1/2 of what they should be. There is almost a hidden 2x factor. 

Unlike my other method, these surrogates and internals are at different concentrations but the surrogate concentration is the same as the internal. Additionally, this only happens with half the surrogates, the middle ones. 

Any explanation?

I have attached some photos.

The one shows how my one qc, same level as my standard 3 is doubling. Calculating the recovery based on response factor has it at approc 74%, 2x what it is displaying. The surrogate and internals all match according to table. 

Also attached is one of the surrogates that is working.

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