Народ, помогите!

Имеется две 3750.
Между ними два канала p2p. настроена балансировка по OSPF, все работает отлично, балансируется, распределяется, красота. Проблемы начинаются, когда один из каналов начинает работать нестабильно теряются пакеты, задержки и т.п.). Про ip sla при такой схеме ничего не нашел.

Схема:

                      -(__C3750_1__)-
               10.77.40.49/30 | | 10.77.40.53/30
                              | |
                              | |
                              | |
               10.77.40.50/30 | | 10.77.40.54/30
                      -(__C3750_2__)-
                                                          
Конфиги:
              
                C3750_1:
              
                interface GigabitEthernet1/0/1
                  no switchport
            ip address 10.77.40.53 255.255.255.252
                  ip ospf cost 1
                  speed 1000
                  duplex full

        interface GigabitEthernet2/0/1
                  description P2P to Gol'evo Nauka-Svyaz'
                  no switchport
                  ip address 10.77.40.49 255.255.255.252
                  ip ospf cost 1

                router ospf 1
                  router-id 10.77.1.1
                  log-adjacency-changes
                  no capability lls
                  passive-interface default
                  no passive-interface GigabitEthernet1/0/1
                  no passive-interface GigabitEthernet2/0/1
                  network 10.77.40.48 0.0.0.3 area 0
                  network 10.77.40.52 0.0.0.3 area 0
                  network xxxxxxxxxxxxxxxxxxxxxxxxxx
                  network xxxxxxxxxxxxxxxxxxxxxxxxxx
                
                 С3750_2:
                
                  interface GigabitEthernet1/0/1
                  no switchport
                  ip address 10.77.40.50 255.255.255.252
                  ip ospf cost 1
                  priority-queue out
              
                interface GigabitEthernet1/0/3
                  no switchport
                  ip address 10.77.40.54 255.255.255.252
                  ip ospf cost 1
                  priority-queue out

                router ospf 1
                  router-id 10.77.8.1
                  log-adjacency-changes
                  passive-interface default
                  no passive-interface GigabitEthernet1/0/1
                  no passive-interface GigabitEthernet1/0/3
                network 10.77.40.48 0.0.0.3 area 0
                  network 10.77.40.52 0.0.0.3 area 0
                  network xxxxxxxxxxxxxxxxxxxxxxxxxx
        network xxxxxxxxxxxxxxxxxxxxxxxxxx