Please, follow the steps below what to check before you send the 2N IP Intercom device for repair:
a) device does not boot up after plug in
b) device is not reachable in the network/can not be found in the Network scanner
c) device is not working correctly, audio issues with microphone and/or speaker
add a) As a first step check out the LED signalization and the electric installation of the device. This can be found on www.wiki.2n.cz section of installation manual and electric installation for each device.
verify that the power source, either the PoE or External power source 12V DC is working correctly
add b) verify the correct Ethernet cabling and also other network components. Try also a different device in the same network
add c) verify a possible mechanical damage of the Speaker itself and also the setting of audio parameters in the section Hardware - Audio
Before you issue the RMA try also a reset of the device, either from programming Menu or a HW reset:
Factory reset - How to do factory reset on 2N IP Intercoms
If you ask for RMA, where is obvious hardware damage, attach photos from the installation side, from the damaged part and another photo which could be important for RMA process.