It sounds like Shanwick Radio 124.175 is off frequency, like if the radio was tuned to 124.170 instead of 124.175 ?
How practical would it be to split up some of these frequencies onto separate feeds ? Great location but can get very busy at times with so much traffic in the area on so many frequencies on one radio.
It would be great if you could split off the Shanwick Radio and Clearance Deivery frequencies onto a separate feed, and also split the high and low sectors as well. (I can donate funds to help).
I see there are two radios in Shannon now but both are scanning some of the same frequencies. Any chance as a test you could put the Shannon Low sectors on the Airport radio only and the Shannon High Sectors and Shanwick on the Center radio only ?