Hi Erno,
The Vivaldi range uses a battery backed RAM/RTC to store unit settings, such as volume, balance, filters etc. It also stores the serial number of a unit, and with the Vivaldi Clock it stores the clock calibration data. If the battery is drained, these settings and data will be lost from the unit. This is where a Vivaldi Clock can show “CAL” on the display. None of these stop the Vivaldi DAC, Clock or Transport functioning normally. With the Vivaldi Upsampler, some aspects of the streamer need a valid serial number to fully boot (such as the Roon Ready module).
At the time Vivaldi was designed, there was no suitable battery-less non-volatile RAM available. By the time we had come to design Rossini, suitable RAM was available so was designed in from then on. This includes Vivaldi Transport II, which uses non-volatile RAM for unit settings.
The battery is not drained while the product is powered on or in sleep mode, and is only used when the unit is fully powered off. However, even switched on or in standby, batteries have a finite lifespan, impacted by things like operating temperature. We have been using this particular part since before Scarlatti, and historically they have regularly lasted >10 years, so we were confident they would perform the same in Vivaldi.
The battery is not user replaceable, and does require a service technician to change. Should a Vivaldi unit lose its settings when powered off, this can be easily rectified locally by a dCS service centre / technician, which your dealer will be able to facilitate.