Anan-7000 MkII freezing during transmission

[GAC]

I received a new radio a couple of weeks ago. It seems to work well in receiver mode however it freezes after a few minutes to a few seconds in transmission. I'm transmitting CW into a dipole which is well matched (SWR< 1.5) on 7m. An Elecraft K3 seems to be very happy in the same environment and the only difference I see is that the Anan has a LDG auto-tuner on the output. The radio and Thesis both freeze in transmission and both have to be turned off and re-started to unlock. Someone has a pointer to a similar thread or suggestions?
George
VE2VAB

[SA3ATF]

It sounds like you have rf feedback.

[Ernie]

What does it do into a dummy load without the tuner?

[GAC]

Thank you all for the suggestions. I added all the toroids I could find and a common-mode filter on the antenna. I also removed any equipment that was not essential. I freezed after 4-5 CQs. Good suggestions w/r to a dummy load however now I get "error starting HPSDR hardware, ...". From what I can read I need to install Bootloader and set a jumper etc. More reading.

Not an easy start for me.