I have taken a closer look to the different signals used to build up the error signal of MICH. I found no explanation so far for the increase on the level noise (Figure 1). Moreover, taking a look to this weekend data, we can see that the spectrum of both 112 and both DCs is the same (Figure 2).

We would like to make a test and come back to the normalization using the other PD and check whether we recover the level of last week or is not dependent on the normalization.