Remedy brings simply switching to another channel. The sounds then clean. When switching back to the original channel, the sound interference is also there to leave.
I'm pretty sure it is the receiver. Opt for another input signal, for example, from Chromecast that disturbances do not occur. The HDMI input on my Toshiba TV used is also OK, about previously ran a DVB-T receiver without any interference.
Before the unit returns under warranty, have a go yet a firmware update to make. For instructions, and the right software can be loaded at manufacturer. The actual update is done via USB stick directly on the device using the remote control.
Due to the excellent image quality, I rate the device with "not bad"