The DSP box on the Hymer side is located under the passenger seat at the factory, the power supply for the amplifier is fed from this (connection 4-pin Molex connector with 3 blue wires). Therefore, the amplifier must still be operated for the power supply.
The ISO cable as well as jack cable can be converted from the previous DSP amplifier, so that only the power supply via the DSP is still guaranteed.
Alternatively, the power connection cable for Hymer incl. factory DSP box can be installed to bridge power supply TV so that full function and power supply is restored. Installing the cable allows the amplifier to turn on automatically when the on-board power supply is activated, also no need to install a new power supply for the TV and uninstall the factory DSP box.