Tivoli Audio One volume problem

Hello People! is the first time that I write on this forum and I am looking for advice.
unfortunatelly I am not an expert with radio.
I have bought some years ago a Tivoli One impressed by the sound and design. I have used for a little while, but then not anymore so much. Few years ago I took it back to life... but unfortunately I noted that the volume was not doing fine... I was jumping from the actual volume to almost zero volume by itself... at the time it was possible to play little bit with the nob and somehow get some volume... I have give up to the radio again... and this days I have desided to check again...

Present day: the volume now is always on the very low low regardless the position of the nob... or better... if I put it to the max the volume is very low... if a turn the nob to the minimum the the low low volume fade to zero...

Actually I have open the radio... I have clean here and there as I could... but I didn't spray any contact cleaner yet ( I don't have at the moment )...

I have try also to connect the headphone jack to the radio... the sound the the headphone is reasonable and when I turn the nob the volume goes up and down...

Someone have some advice or information? If possible I will love to save the radio...

Thanks

Marco