SS TWR takes forever to start reporting distances

Hello, I’m doing an implementation of SS TWR using the DWM1000 and using the SS example code have managed to get the initiator and responder to talk to each other, with one difficulty. When I start the initiator and responder using the ss_init_run and ss_resp_run methods, they generally take forever to “hear” each other. The initiator merrily blinks away and eventually the responder responds with the proper package and the distance then gets reported. But this can take two minutes or more. The calls to ss_init_run and ss_resp_run are initiated using a timer (on two separate devices of course) and I’ve played around with the timeouts of these timers a bit and sometimes it appears this makes a difference, but the results are not consistent enough to get a good feel for what works and what doesn’t. Both timers have a period of about 500ms. This is on a system with a Nordic MCU as host. Any suggestions?