I have the same issue. Both on the 32 and 64 bit version.
This morning I reinstalled again (64 bit) and after first test it took 7 minutes till it didn’t showed the callsigns anymore in Jtalert 2.16.5.
Second time after restarting it all it took much longer, about 40 minutes or so.
Hope you can send me the fix too Laurie so I can test that out.
Thanks in advance,
Ivan , PD0AI