[App_rpt-users] control of the tx tone

Hi! I am using the dsp fonction of the app_rpt as core and tone. And I am using the tone output by the URI to encode my ctcss tone. All is working ok, but I have a few friend that use my repeater with some cross band repeater radio. And they have difficulty cutting in cause they have to wait after the tail and ct. before there cross band repeat radio give them the chance to tx back at the repeater. On my old rc-210 we were able to stop encoding the ctcss tone while the courtesy tone and tail of the repeater..So they were runnign ther xband radio on tone squelch on rx and the tx on there side was fast and sharp. Is there a way to do the same with app_rpt? Pierre VE2PF