I used to have this issue as well about 3-5 times a day.
Yesterday I found this comment
https://displaylink.org/forum/showpo...6&postcount=19 about modifying /etc/pulse/default.pa and it seems to have solved it for me - no problems so far today.
(Dell Precision 5530, Dell D6000 dock, Ubuntu 18.04.3, displaylink-driver-5.2.14)