I was at New London, CT and Charleston, SC. I did a single boomer cruse out of Holy Lock, Scotland USS L. Mendel Rivers (SSN 686) USS George C Marshall (SSBN 654) USS Gato (SSN 615)
+1 I was stationed aboard both and they are very quiet. The boomers (nuclear missile boats) also travel at very slow speeds. I would say they were probably playing games lost each other in the thermal layers. Which is quite easy to do.