Ты путаешься, где попало.  ?? 

Ну здесь ещё как-то эмоции можно передать.

А вот вроде бы нейтральное

The times they are a-changin' .

http://bob-dylan.org.uk/archives/1589

И скорее всего здесь подразумевается не причастие, а существительное в значении "тот, кто всё портит".

ты, паря, не в своё дело встрял

встрял, куда тебе встревать не положено

In the same way, French songwriters sometimes 'stretch' some of the words in their lyrics to suit the music by pronouncing final 'e' s in words as a separate syllable. So, for example, "je t'adore" (=3 syllables in standard spoken French) becomes "je t'ador-e" (=4 syllables) in some songs.

Here's one of the many discussion one can find online:https://english.stackexchange.com/questions/5248/the-times-are-a-changing-why-a

Hmmm, that's an interesting link. I don't know anything about Appalachian English, so can't comment on this. I've seen comments online linking these two, but I suspect that only Bob Dylan knows whether this influenced him when he wrote this song. However, many other songwriters (inc British ones) have inserted a- prefixes into their lyrics over the years. They can't all be influenced by Appalachian English!

I'm sure you're right that in C16th English the a- prefix equated [in some cases] to something like 'in the process of ......ing'. The word 'adrift' comes to mind, for example. However, I don't accept that the a- in words such as 'about', 'around', etc, nor an a- placed before a verb (eg kissin' -> a-kissin') has any such meaning or nuance 400-450 years later in modern English. Note also that where they do appear in modern English, it's nearly always in songs. In my view they're nearly always inserted to 'stretch' the line, just as 'And ......', 'Oh ......' etc inserted at the beginnings of lines in lyrics often do -- to add a syllable.

I reckon that if you asked present-day (or even 1960s) English-speakers if there was any difference in meaning between a-messin' v. messin' and a-changin' v. changin', nearly all would say "there's no difference". To quote one of the correspondents in your link: "I feel like Bob Dylan probably used it for metrical effect [my underlining] ... certainly I don't think you'll find anyone who could find any difference in meaning between Bob's lyric and just 'the times are changing'."

On the other hand, it's also an extremely convenient way of adding an extra ('filler') syllable to the line without (in my view) changing the meaning....

You say that "Having no meaning would mean that a-changin' is the same as changin', which is not the case". Isn't it? What's the difference in modern English, then? Remember that both songs mentioned by the asker -- The Times They Are a-Changing and These Boots Are Made For Walkin' -- were written in the 1960s, not the 1500s.

*Captain Obvious mode off*

That's about as much as I can safely assert: i n all the finer shades of perception I defer to you as a native speaker (it's your language, after all, not mine :) ).

I'd agree that, stylistically, the a- prefix may in some cases make a song appear dated -- possibly because of old songs such as A-Hunting We Will Go (an C18th fox-hunting song which became a nursery rhyme). However, nowadays -- imho -- 9 times out of 10 the a- is just inserted as a (meaningless) filler. After all, if you were writing the lyrics to a tune you'd composed, and you'd thought up the line The times are changin' (5 syllables) but needed two more syllables, you'd be very tempted to lengthen it to something like The times, they are a-changin' (7 syllables). That's what I suspect has happened in the asker's two examples, although I'm not an expert.

I must ask Bob Dylan and Nancy Sinatra about this the next time I bump into them!

I had seen https://english.stackexchange.com/questions/5248/the-times-are-a-changing-why-a , it was actually the only one I was able to find on the topic, not one of the many.  

 Right, I’ve only seen it in songs, with one exception: 

BBC Radio ages ago used to have an English teaching  programme called Professor Grammar. There I heard him exclaim, Time’s  a’wasting, time’s  a’wasting! (Might have been wastin’, not sure.) 

I felt, too, the  form is marked stylistically in today's language, and I was curious to find the Russian way to portray the style. 

If it’s vernacular English what would be vernacular Russian?

 I thought someone could have an idea.

a-messin' obviously isn't part of standard (spoken or written) modern English. When writing These Boots Are Made For Walkin' the songwriter could possibly(?) have been trying to replicate the style of some local US dialect, but it's a very simple pop song with unsophisticated lyrics (unlike The Times, They Are a-Changin', which has more meaningful lyrics, being a commentary on changing social attitudes in the 1960s), so I somehow doubt it. I'm not an expert on US dialects, though, so will leave this to others.

Fascinating stuff, thank you.   

Рина Грант, 

Где ж тут как далеко, тут и ногой не ступили. Да, передавать стиль или диалект трудно, высший пилотаж, но интересно как исполнителю, так и наблюдателю.   

Задача не решена. Что ж, не трагедия. Может, она не имеет решения.  

 Всем большое спасибо за участие.

пример запомнился с детства - у нас дома был однотомник пьес Мольера (дореволюционное издание), где содержалось и следующее:

https://vadim-i-z.livejournal.com/3455103.html