speaking

For the most part I don't believe in attributive uses of nouns, I consider them to be the modifiers in a compound noun. Other Germanic languages have the same structure, but we call them compounds, so there's no reason not to do the same for English.

I only consider the first and third adjective sense to be a compound, judging by the usage examples. In both usage examples, the word speaking has a genitival meaning: voice of speaking, part of speaking. This does not work for the other two, which are uses of the participle, adjectival in nature rather than nominal. In sense 2 there isn't even a modification of a noun, so it can't be a compound, and the presence of more flags it as clearly adjectival.

In sense 4, there's two different usage examples, but these are syntactically different. In speaking parrot and speaking clock, it's just the standard use of the participle to qualify a noun, which all present participles can do and is thus not special. The examples for the subsense "in compounds" seem like uses of the participle directly as the head of a noun-participle compound, along the lines of food-eating, latte-sipping, house-building, rocket-launching, Wiktionary-editing and a near infinite number of other noun-participle combinations one could think of. All of these compounds have a meaning in which the modifying noun is the direct object of the verb it's attached to.

So I think sense 4 shouldn't even be there, it's a transparent and predictable use of the participle. Senses 1 and 3 reflect the gerund, so they probably shouldn't be there either. Only sense 2 appears to me to be clearly separated from the meaning of the verb.