First attempts to use the last version (IV) of the Domino Ring Sampler (DRS) chip for time profile analysis of PMT signals produced in dual-readout calorimeters are described. Time characteristics of the signals sampled with a simple DAQ system based on evaluation boards with the DRS-IV chip are compared with those of equal signals processed with a high performance digital oscilloscope. Separation between the fast Cherenkov and the slow scintillation components in the light signal produced by high energy electrons in a BGO crystal calorimeter is studied with data acquired with the two DAQ systems in identical beam and detector readout conditions. Studies of the pulse rise time and of the signal decay tail are presented in a time window of about 400 ns at sampling frequencies in the GS/sec region. Very preliminary results of timing performances of a prototype of a commercial board based on the DRS-IV chip are also presented; this board was used to digitize the readout signals of a prototype module of a new Dream fiber calorimeter. Preliminary results show that the performances of the DRS based DAQ systems are equivalent to those of a digital oscilloscope and that DRS-IV based digitizers can be successfully used for different applications in dual-readout calorimeters.