Finally get fixed, mac address problem. Thanks.
Found that Roon checks for every network interface mac address , EVEN if some interfaces not in use (no ip address/netmask configured, link state down).
In my situation, there is a bond0 virtual interface, changing its mac-address after every reboot.
--- mac-a 2019-12-13 11:10:57.000000000 +0800
+++ mac-b 2019-12-13 11:10:57.000000000 +0800
@@ -1,7 +1,7 @@
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: bond0: <BROADCAST,MULTICAST,MASTER> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
- link/ether fa:bd:20:ca:ab:ea brd ff:ff:ff:ff:ff:ff
+ link/ether 8a:05:c8:08:ca:89 brd ff:ff:ff:ff:ff:ff
3: eth0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc fq_codel master br-lan state DOWN mode DEFAULT group default qlen 1000
link/ether 00:xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff
4: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP mode DEFAULT group default qlen 1000