Increasing lag time between capture ready beeps

Anyone else with an H25/H20 running capture one on a PC have this problem? We have a case number on it, but no action. The lag between capture readiness beeps starts at about three seconds, then the next lag is 5-7 seconds, then 7-10 seconds, then every subsequent lag is 15-25 seconds. This is if you fire off a shot immediately after the beep each time. We've tried it on our Mac (silver bullet g4) and have no problem, but on the field machine (Toshiba Satellite PC) and another Wintel Tower, we just can't get a satisfying capture rate. Just want to know if we're alone here...?