Re: uBitX V6 only transmits double sideband
Other than shipping, missing parts, or physical damage, all support for the uBiTx products is on this message board. All are volunteers, so I would suggest that you take that into consideration. This keeps the overhead costs down for HFSignals, and the price of the rig. There are thousands of years of radio experience on this board. A number did it as a profession. Because it is via email like communication, it can take longer than a phone call, however, there is a high success rate on problem-solving with this process.
Here are two links that could help in the calibration and configuration of the v6:
First the directions from Ashhar Farhan one of the originators of HF Signals
Here is the BFO tuning aid that is discussed in the above video:
The above solves most of the problems that you describe.