ML 335 and DCS delius

Hi, I have a dcs delius driving directly my ML 335. Whenever the dcs activates a relay (for example muting or changing filters), there is a clear "CHSK" in the speakers. I have tried changing transports, earthing arrangements and so on. I then called Levinson who said the 334 335 336 series do not have input capacitors as levinson thought it affected the sound. Could it be the "CHASK" is normal in such a situation?