diff --git a/samples/bluetooth/hci_ipc/nrf5340_cpunet_iso-bt_ll_sw_split.conf b/samples/bluetooth/hci_ipc/nrf5340_cpunet_iso-bt_ll_sw_split.conf
index 2b2b1348ccb..6c28a4537e6 100644
--- a/samples/bluetooth/hci_ipc/nrf5340_cpunet_iso-bt_ll_sw_split.conf
+++ b/samples/bluetooth/hci_ipc/nrf5340_cpunet_iso-bt_ll_sw_split.conf
@@ -5,7 +5,7 @@ CONFIG_ISR_STACK_SIZE=1024
 CONFIG_IDLE_STACK_SIZE=256
 CONFIG_MAIN_STACK_SIZE=512
 CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=512
-CONFIG_HEAP_MEM_POOL_SIZE=1024
+CONFIG_HEAP_MEM_POOL_SIZE=4096
 CONFIG_CBPRINTF_REDUCED_INTEGRAL=y
 
 CONFIG_ISR_TABLES_LOCAL_DECLARATION=y