A third commentary on using the IC706 MkIIG for WSJT:
Turn off any audio processing on the transmit side. No compression, no narrow filters in the audio path or RF chain.
If you are using either the 6 pin Mini-DIN or the 13 pin ACCY interface connector you MUST set menu option 29 to 1200 baud. (CAUTION - When you do a radio reset this gets changed back to 9600!)
To avoid frying the final transistors, keep the output power no higher than 40%. (CAUTION - When you do a radio reset this gets changed back to full power!)
If you see audio in the waterfall but get no decodes, there are two common problems: 1) The radio got set to LSB instead of UPPER sideband. 2) Your computer clock is off by two seconds or more.
And as someone else mentioned, check that the computer's USB audio sampling rate is set to 48 kHz, NOT the Microsoft default of 44.1. That applies to both the transmit and receive sides of your computer's USB port, you have to set BOTH correctly!

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Karl  WA8NVW  OH
WA8NVW@...
in WSJTX@groups.io