diff --git a/repos/os/src/server/nic_router/component.cc b/repos/os/src/server/nic_router/component.cc
index f86cac3a3f..3be7ea3f4c 100644
--- a/repos/os/src/server/nic_router/component.cc
+++ b/repos/os/src/server/nic_router/component.cc
@@ -115,14 +115,13 @@ Net::Session_component::Session_component(Allocator           &alloc,
 Net::Root::Root(Entrypoint        &ep,
                 Timer::Connection &timer,
                 Allocator         &alloc,
-                Mac_address const &router_mac,
                 Configuration     &config,
                 Ram_session       &buf_ram,
                 Interface_list    &interfaces,
                 Region_map        &region_map)
 :
 	Root_component<Session_component>(&ep.rpc_ep(), &alloc), _timer(timer),
-	_mac_alloc(config.mac_first()), _ep(ep), _router_mac(router_mac),
+	_mac_alloc(config.mac_first()), _ep(ep), _router_mac(_mac_alloc.alloc()),
 	_config(config), _buf_ram(buf_ram), _region_map(region_map),
 	_interfaces(interfaces)
 { }
diff --git a/repos/os/src/server/nic_router/component.h b/repos/os/src/server/nic_router/component.h
index 06cf99ea17..c6a6f276d4 100644
--- a/repos/os/src/server/nic_router/component.h
+++ b/repos/os/src/server/nic_router/component.h
@@ -157,7 +157,6 @@ class Net::Root : public Genode::Root_component<Session_component>
 		Root(Genode::Entrypoint  &ep,
 		     Timer::Connection   &timer,
 		     Genode::Allocator   &alloc,
-		     Mac_address const   &router_mac,
 		     Configuration       &config,
 		     Genode::Ram_session &buf_ram,
 		     Interface_list      &interfaces,
diff --git a/repos/os/src/server/nic_router/interface.cc b/repos/os/src/server/nic_router/interface.cc
index 8f9615a8b4..4aa3f0a3eb 100644
--- a/repos/os/src/server/nic_router/interface.cc
+++ b/repos/os/src/server/nic_router/interface.cc
@@ -198,6 +198,7 @@ void Interface::_pass_prot(Ethernet_frame       &eth,
                            void          *const  prot_base,
                            size_t         const  prot_size)
 {
+	eth.src(_router_mac);
 	_update_checksum(prot, prot_base, prot_size, ip.src(), ip.dst(), ip.total_length());
 	_pass_ip(eth, size_guard, ip);
 }
@@ -416,7 +417,6 @@ void Interface::_adapt_eth(Ethernet_frame          &eth,
 		new (_alloc) Arp_waiter(*this, remote_domain, hop_ip, pkt);
 		throw Packet_postponed();
 	}
-	eth.src(_router_mac);
 }
 
 
diff --git a/repos/os/src/server/nic_router/main.cc b/repos/os/src/server/nic_router/main.cc
index 277b540b35..1ff5d5d881 100644
--- a/repos/os/src/server/nic_router/main.cc
+++ b/repos/os/src/server/nic_router/main.cc
@@ -41,7 +41,7 @@ class Net::Main
 		Reference<Configuration>        _config         { _init_config() };
 		Signal_handler<Main>            _config_handler { _env.ep(), *this, &Main::_handle_config };
 		Uplink                          _uplink         { _env, _timer, _heap, _interfaces, _config() };
-		Root                            _root           { _env.ep(), _timer, _heap, _uplink.router_mac(), _config(), _env.ram(), _interfaces, _env.rm()};
+		Root                            _root           { _env.ep(), _timer, _heap, _config(), _env.ram(), _interfaces, _env.rm()};
 
 		void _handle_config();