Calls dropped for 40 seconds when a distribution switch hung. Design it under a second

A contact center's voice VLAN 110 (10.10.110.0/24) is served by two Catalyst 9500 distribution switches with HSRP group 110: DSW1 (10.10.110.2, priority 110, active) and DSW2 (10.10.110.3). Both run OSPF to CORE1 over routed 10G links with default timers, and HSRP uses default timers. Last month DSW1 hung after a software fault with all its links still up, and calls dropped for about 40 seconds. The business wants any single distribution failure to cost less than one second of audio.