Routing phone call audio through external audio system

[momo2000]

I’m sure someone has solved this, but searched several ways without success.

I have an HTC device with an USB out for headsets. I want to be able to route the phone conversation through an audio system so folks in the room can hear both sides of the conversation. I tried USB to 3.5mm adapters, but it seems that this scenario is used for listening to the media player, and not for the “phone calls”. Any thoughts on how to do this with adapters/converters?

If this has already been done, a URL referral would be great.

Thanks,
MOMO2000

[Rudegar]

normaly when in headset mode
be it wires using extUSB or bluetooth
all audio that otherwise would be played
by the speaker is played by the extusb or bluetooth headset
at least that how it's been working for me
since xda2

[momo2000]

Agreed, but I am having trouble finding adapters. All the USB to 2.5/3.5mm are for "music" and don't seem to work when in "a call". Thoughts?