[c-nsp] Link down affecting BGP peer

[Hank Nussbacher]

I have 4 individual links defined as part of a Bundle-ether (IOS-XR  
5.3.3 on ASR9010):

interface TenGigE0/2/0/1
  bundle id 2 mode active
  flow-control bidirectional
  carrier-delay up 100 down 4000
! They are all part of a bundle...
interface Bundle-Ether2
  mtu 9192
  bundle minimum-active links 2

When I shut off just 1 of these 4 links - the bundle stays up yet 
certain BGP sessions flap for about 5 seconds - different peers 
depending on which of the 4 links gets turned down.

My BGP config:
router bgp 378
  rpki server x.139.197.151
   transport tcp port 8282
   refresh-time 600
  !
  bgp log neighbor changes detail
  address-family ipv4 unicast
   bgp dampening 5 750 3000 10
   bgp attribute-download
!
  neighbor x.x.125.1
   remote-as xxxx5
   address-family ipv4 unicast
    send-community-ebgp
    soft-reconfiguration inbound

What could be causing the bgp peer to flap even though the LAG stays up?

Thanks,
Hank