Don't really know, I only call one number there which is 703-759-xxxx (my daughter).
I had the same problem 3-4 weeks ago. I left all the details in ticket number QRM-754256 yesterday (Thurs) around 6PM EST including a tracert right after it happened as requested by Brandon the last time it happened. That has been a problem number since day 1 with echos and no audio one or both ways.
Edit: Are you aware that entering a < or a > sign (as is always included in a TRACERT) into a ticket cuts the text off exactly at the point of that symbol and nothing past it gets saved? If you look at the ticket listed above make sure you read back 4 or 5 updates because it took that long to figure out why my tracert (and anything after it) never got saved.
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