Let’s suppose someone goes to a certain street and plays an audiobook recording about their political program every day on the speakers at loud volume. If someone walks up and switches the recording off so that it stops playing and causing a nuisance to everyone until they walk back down to the end of the street to put it back on, is the person turning it off committing any sort of crime?
...an intentional interference with another person's lawful possession of a personal property. A "chattel" refers to any personal property, moving or unmoving. Trespass to chattels does not apply to real property or any interest in land. In order to prove trespass to chattels, you are required to show the following elements:
Intent to trespass: Merely intending to do the act is enough to show this element of trespass. You don't necessarily need to show intent to harm a specific person.
Lack of owner's consent: There must be an unauthorized, unlawful interference, which means the person interfered with or dispossessed the chattel without the owner's permission.
Interference of chattels: A person commits a trespass to chattel by (1) dispossessing another of the chattel, (2) using or intermeddling with a chattel in the possession of another, or (3) damaging the chattel. Interference does include dispossession of a chattel, but it must be something short of conversion.
Whether it would be actionable is another question as de minimis non curat lex
Although the above link is from an American site, it mirrors the UK definition and is the best and most succinct explanation I can find
In most jurisdiction there is no specific law against touching another person's property without harming it.
On the other hand, the person playing the recording may well not be committing any crime either. In some places there are anti-noise laws which apply if a recording is played at more than a specified volume. In some places there are laws against "nuisances" which are variously defined.
For a somewhat similar fact pattern, see Cantwell v. Connecticut, 310 U.S. 296 (1940) in which a person played a recording of a speech about religious views, and was arrested for "breech of the peace" when others present objected.
It's not illegal or a civil wrong. You can either call the Police as its a public order offence to make noise above certain decibels in residential areas, or turn it off yourself. If the content is offensive or propaganda you are well within your rights to prevent the longevity of that crime. As long as you do not cause damage to the speaker you are simply stopping a crime in progress. If they want to turn it back on you can turn it off. I wouldn't recommend doing that though because you'll most likely end up I a hostile situation with the owner\user. Better to call the Police.
4Fear or provocation of violence. (1)A person is guilty of an offence if he— (a)uses towards another person threatening, abusive or insulting words or behaviour, or (b)distributes or displays to another person any writing, sign or other visible representation which is threatening, abusive or insulting,with intent to cause that person to believe that immediate unlawful violence will be used against him or another by any person, or to provoke the immediate use of unlawful violence by that person or another, or whereby that person is likely to believe that such violence will be used or it is likely that such violence will be provoked. (2)An offence under this section may be committed in a public or a private place, except that no offence is committed where the words or behaviour are used, or the writing, sign or other visible representation is distributed or displayed, by a person inside a dwelling and the other person is also inside that or another dwelling.