Alignment of 1310nm probe

Kuroki,

I aligned for probe laser(1310 nm).
I changed the IU alignment and scanned.
I got the result like this figure.
In it, the measured peak AC signal value (~0.006 V) is lower than before(~0.02 V).
Also, secondary peak can't be seen well.
Next time, I have to align again in order to get a good result.