Because it IS of minor importance, because of it's non-directional properties - positioning of the sub is no different to positioning of any bass speaker, although as the wavelengths involved are VASTLY larger than any living room I wouldn't suggest it's particularly due to the 'wavelengths' involved.

But this is all well beyond the scope of this thread, and hopefully he's tried moving it closer to see if the BlueTooth keeps working OK then.

Thinking this way is ignoring the fact that where a sub is placed in a room can have a positive/negative affect on the output, there will be a sweet spot where it sounds best, an optimal position - this is because room response, reflections and wavelengths all have an affect on how a sub performs, the room can boost certain frequencies and null others depending on where the sub is placed, that's why subs can be problematic when trying to integrate/set them up.

Ultimately you are after a flat response and you only get that by experimenting with different positions.

We are talking sub frequencies where the wavelengths can be in excess of 20m, not 7 or 8m which is typical of a normal full range speaker. If you are referring to your HiFi speakers they could be problematic too if outputting sub frequencies.

If you want good performance from a sub it's important to find the best position for it, if on the other hand you are not that bothered, just stick it anywhere.