[OOC] Return to the Rusty Rat

[Torin]

A question about sculpt sound. I haven't checked the details before but this time I did. What the description says,

You change the sounds that creatures or objects make. You can create sounds where none exist, deaden sounds, or transform sounds into other sounds. (...)

My question is about what is the intended interpretation (RAI) of "sounds that creatures or objects make".
I mean that the spell is cast on the party members, and when a subject of the spell kicks up pebbles or breaks a twig then is it the character, or the pebbles/twigs that make sound?
I'm not saying (at the moment) that the spell is overpowered. My instant instinct is to compare to Extended Silence which is same level but waaay more restricted, probably beyond comparison (emanation and not subjects; much less duration; and cannot pick what to deaden and what to keep).
So...

Are there similar spells with similar effects whose power levels are comparable?
Is there a FAQ, errata, or other official article explaining "Rules As Intended" here?
I leave hunting for clues to you. Any insights are welcome, and a proper argument (pro/con) is worth that particular "OOC XP" I mentioned earlier.

http://www.enworld.org/forum/showthread....-questions

It's bardic exclusive spell. So it should be compare with a 4th level spell.