The SAFARI instrument is a spectrometer on board SPICA, using ~4000 TES bolometers with an unprecedented sensitivity. We are currently optimizing an FDM readout prototype for SAFARI, which is capable of reading out 160 pixels with the bias frequency range 1-4 MHz and 16 kHz spacing. We present our latest results with emphasis on the noise and cross-talk performance of this system. The measured readout noise is discussed in various configurations. We also present a method for mapping out the electrical cross-talk between the pixels in the array and elaborate on the measured data and analysis.