The spectra of CS_ACC_LVEAFLOOR_YCRYO_Z, CS_ACC_HAM3_PR2_Y are much lower than the other accelerometer channles.

(i) The channel CS_ACC_LVEAFLOOR_YCRYO_Z has been like that since March 12. 

(ii) The channel CS_ACC_HAM3_PR2_Y has been like that since Jan 30. 

It seems they are either disconnected or having a lose connection.