It turns out there are no reasonable signal from the segment 1 on the IP_ANG QPD.
For right now I can still use it as a funny QPD, but I absolutely need somebody to check and fix it in a daytime.
IP_ANG is supposed to be acquired at c1auxey (east end), but actually it had been at c1auxex (south end).
So I fixed it by editing the db files (i.e. ETMXaux.db and ETMYaux.db). Now it seems working fine.