That whistling sound...

...was the shithammer coming down on Respironics, the makers of the CPAP mask that Rico is forced to wear, due to his sleep apnea, via Apria Healthcare, his provider.
As noted in the 1.11am email to Apria:

Okay, I was just kidding before, but now I'm pissed.
You could've replaced that mask from Respironics when I asked you to, but nooooo, I had to wait for some arbitrary time limit, which has another week to go.
Now, however, that POS mask is not merely malfunctioning, like usual.
It's broken.
Which means that, since it's 1.15am on a Saturday, no one there will read about this (nor care) until Monday.
This, needless to say, is not making me any happier.
My intention was to send the mask (smashed into small pieces, if possible) to Respironics once I got the new one. Then I realized that that was childish and petty, and decided not to do that.
That, of course, was before.
Now, of course, it would become a suppository for someone at Respironics, if only I could figure out how to deliver it, and it's definitely going to them, in tiny pieces, as soon as a new one arrives.
Did you get it that I'm mad as hell and I'm not gonna take it anymore? (That's from "Network", in case you didn't recognize the line.)
Good.

Rico says he can be verbose when he's mad...