I hear this often on RAI as the lead in to a segment-- is it literally "in so much (so many)??

It's "intanto" and it means "in the meantime" or "while" like in
Intanto che aspetti fai una telefonata
While you wait make a phone call

Grazie mille Giulia. I never thought to put it together.

Giulia, why is it "aspetti fai" and not "aspetti fare" ???

Intanto che aspetti (while you wait), fai una telefonata!!! (make a phone call!!!)
Fai is Imperativo.

I suppose that the doubt you have is about a sentence like:
Intanto che aspetti DI FARE una telefonata, puoi raccontarmi cosa hai fatto ieri.
While you wait to make a phone call, you can tell me what you did yesterday.
Am I getting your doubt right?

While I agree with Giulia that you probably heard "intanto", one word, "in tanto" exists nontheless.

Think for example
in tanto disordine sulla scrivania non riesco a trovare il dizionario.


In tanto fracasso era impossibile sentirci.

where your first guess would be right: so much

thank you - the imperativo gets me every time!