The animations on the unique head T_B_De_UNI_HeadArchmatronTR (used for Alvu Sareleth in Necrom, High Offices) are broken: occasionally she blinks very rapidly, gets "frozen" with her mouth wide open or her eyes closed for ~1sec each. The model T_B_De_HeadFemTR_49 (which afaik is based on the unique one) does not seem to be affected.
I may have found a potentional conflict between Temriel Rebuilt and 'ANY' other mod that uses lua code for spells.
It maybe you are using the default "event.register("spellCast", spellCastCallback)" which can and will conflict with 'ANY' other mod that also uses it.