If you pull up the interactions and review the timelines, you can see how long it attempted each user. As Paulo mentioned, the detection can be an issue. So can cell carrier service and other carrier issues on both ends. Bumping up the time may help with some users, but others still may time out sooner. The timeline includes the total time attempted. If the timeout is set for 10 seconds, but the call setup took 5 seconds, it will only actually ring for 5 seconds. They may answer a split second too late and it already routed to the next user. Some cell carriers will send the call to voicemail after x seconds, while others will do so after y. If it goes to VM, and they aren't the last agent in the rotary pool, then it is their cell VM and it was not detected.
I'm sure you've explored this option, but the best bet is to have them use WebRTC phones. Lot's of users are using their personal laptops and Chrome with the WebRTC phone and a headset.
Maybe you can get some groups moved over and change the other groups to broadcast. Also, if you have a ton of groups, you could use the API and loop through each group updating the ring type.
Thank you,
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Daniel McLeod
Qsect LLC
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