Music Match and Recording Control

I use rca left and right cord to plugin to input of computer to record some recorded music from cassette to make into mp3.

Each time I click Strat Copy in Music Match the select Aux/Line in 2 which originally was ticked off is unticked each time I click Start Copy button in
Music Match. So each time I record music from cassette I have to click select
again in order to record. Why is it always unchecking the select box in my computer?

Thanks.