Distorted WSJT FT8 transmit signal

I am using a Flex 6400, SmartSDR v3.2.39 and WSJT v2.5.4.
I can receive and decode signals and I can make contacts however I see that my transmit signal is distorted and have gotten reports of the distortion. I have not been able to make any adjustments to clear up the distortion. The attached screen print, Distorted Signal, shows the distortion. This is the signal when transmitting a message. The attached screen print Tune TX 1500hz shows the signal when tuning on 1500hz. This looks good however the interesting thing is that if I move the transmit offset to 1501hz it becomes distorted, see attachment Tune TX 1501hz. This problem occurs on multiple bands and either into an antenna or dummy load. I have also attached the DAX and Radio Panel screenshots.

Has anyone had the same type of issue and what was done to correct it?

If you need more information on my set up please let me know.

Here are some of the settings that I have for WSJT and Flex
WSJT-x v2.5.4
-Settings
--Radio
---Rig: FlexRadio 6xxx, Poll inteerval 1s
---Cat Control Network Server: localhost:5002
---PTT Method: CAT
---Mode: None
---Split Operation: None
--Audio
---Input: DAX Audio RX 1 (FlexRadio Systems DAX Audio) Mono
---Output: DAX Audio TX (FlexRadio Systems DAX TX) Mono
Flex Radio 6400
-SmartSDR version 3.2.39
--DAX
---TX Stream: TX Gain 48
---Mic Stream: Mic Record Gain 48
---RX Streams Slice A: RX Gain 34

Thanks Dave KW1DX