FSX PMDG 777 radio stack query

Recently reloaded my flightsim gear after a pause due to illness.
However, my problem is :
If I tune my radio active into, for instance, Heathrow tower and the standby into 122.80 I get no response from tower.
But if I tune my active to 122.80 and the standby to tower I get a response.
Can some member advise what may be going wrong here and suggest a remedy please?
Thank you

maybe you are transmitting on the comm 2 ?
a screenshot of your pedestal radio and from the pilot client would help understand what you have selected

here it is

I apologize if this is quite obvious and you’ve already checked, but just to cover all bases…

  1. Are you certain ATC was online when you tried Tower?
  2. Are you certain that Heathrow Tower responded to you when you called on Unicom, or was someone one Unicom responding to you?

Hello Don and thanks for your input. Yes, I am sure ATC was online as I was given a 5//5 reply.
I have checked again today and if I enter `UNICOM into the active and HEATHROW live ATC into standby……I get a response.
It looks like my radio stack is working in reverse but it looks like I shall have to work in this mode!
I dont think there is something I can do to correct this……short of un installing FSX/SE which I am not considering.
Thank you

can anybody help please?

With the radio stack in that precise configuration, what does your pilot client show as your active frequency on COM 1?


hello DON
I am still having this problem. Have been on various forums but nobody seems to be able to help me. Although the TX window lights up when I press the ptt button, ATC cannot hear me. My v pilot settings are all correct.
This is very frustrating as it looks like I am doomed to fly from now on in silence!
Have you any other ideas please?