VoLTE x NR throughput

When VoLTE call is initiated, NR throughput becomes low.
Is there a way to tackle this?

Have u checked the split bearer and its ARP configurations for endcprofile?
Split per UE allowed or not allowed during VoLTE setup.
If it’s set to split per UE not allowed… than SN uses MN entities for QCI9.
Here chances of low throughput and in next mobility SN resources will be released to maintain VoLTE call.

Is the NR removed during the call or stays intact with KeytoUse Secondary?