I immediately add the review to catch potential interested parties!
I will come back after contacting the store (it is closed now).
Regarding the review.
It makes a terrible noise, FAR AWAY.
Maybe it's because of its power supply (it's a jack..! yes, a plug that connects to the amplifier with a mini jack ending like the headphones for mp3 players, etc. - only that this one shows a "mono" jack).
Maybe it's because of the adapter they provided, because the AC (jack) power supply has a UK plug.
I tried, of course, to connect it to different sockets in the house, which never had an issue, and it still produces a very loud noise. We don't mean that it's just not audiophile or hi-fi, it's very intense and high in volume!
I will ask for a replacement, because I am patient and because it has some positives, such as its small size, compact design, beautiful appearance with the metal casing, and the on/off switch.
I will see how the store responds and then I will come back.
I also tried with another EU/UK socket adapter that I had, no change.
As for its performance, of course, I couldn't evaluate it with so much noise...
The fidelity of the sound transfer from the turntable seemed satisfactory (maybe even better) for the price of the product, and the volume it provides (it doesn't have a potentiometer, just one volume level, 'full-on') is moderate to good. I didn't lack volume, but it definitely doesn't play very loud. The preamp is borderline here too, but honest.
I will return immediately.

Update A (April 6):
I spoke with the store who kindly referred me to "directed electronics" (Thessaloniki) as 'the service' which, from what I understood, must be the product's importer. Their call center and technical department were initially very polite and told me that they will investigate it to find a solution without me having to send it to them. I am expecting an update today or tomorrow.

Update B:
The problem improved with the use of batteries (it also takes batteries and functions as a portable device), but I was really disappointed with the device and the provided adapter, and I got tired of dealing with shipping and expenses to and from Thessaloniki.
I don't have a final picture of whether the importer would eventually replace it, if they would send another adapter, etc. So much time wasted for a mediocre and problematic product, also the importer's fault.