Golf 6 gti radio sounds dull (bad reception since factory reset)

Hello,

I have an original golf 6 gti imported from Germany, which I have owned for 2 years now. Radio sounded very clear in the beginning, good reception loud enough but not long after I factory reset the radio (wanted to take off French channels) it started to sound duller.
1 Speaker was already broken in the left door, but the radio sounded quite ok. Now it sounds dull, vague (bad reception), and like there is a radio playing further up in your room.

Any idea how I can fix the audio again, maybe the settings such as antenna are back to original settings as they are focused for reception in Germany, is that possible?
Or maybe the radio is simply dying ?

Here are the VCDS error codes:

Address 56: Radio (J0506) Tags:. 1T0-035-680.clb
Part No SW: 1T0 035 680 L HW: 1T0 035 680 B
Component: RNS-MID H42 5274
Revision: AB001001 Serial number: VWZ6Z7L4091086
Coding: 00050440040000D00000
Shop #: WSC 12345 123 12345
VCID: 377D9EDB864D8D3EE2-8062

Subsystem 1 - Part No: 1T0 919 859 B
Component: EU West V12 8195

3 Faults Found:
02873 - Control Module for Backup Camera (J772)
004 - No Signal/Communication - Intermittent
Freeze Frame:
Fault State: 00100100
Fault Priority: 5
Fault Frequency: 7
Reset counter: 183
Mileage: 128024 km
Time Indication: 0

00856 - RadioAntenna
007 - Short to Ground - Intermittent
Freeze Frame:
Fault Status: 00100111
Fault Priority: 5
Fault Frequency: 4
Reset counter: 181
Mileage: 129416 km
Time Indication: 0

00821 - Antenna 2 for Radio (R93)
007 - Short to Ground - Intermittent
Freeze Frame:
Fault Status: 00100111
Fault Priority: 5
Fault Frequency: 1
Reset counter: 181
Mileage: 129432 km
Time Indication: 0

Thanks in advance!