diff --git a/device/device.go b/device/device.go
index 99f5e60..e7d70c4 100644
--- a/device/device.go
+++ b/device/device.go
@@ -49,8 +49,9 @@ type Device struct {
 	}
 
 	peers struct {
-		sync.RWMutex
-		keyMap map[NoisePublicKey]*Peer
+		empty        AtomicBool // empty reports whether len(keyMap) == 0
+		sync.RWMutex            // protects keyMap
+		keyMap       map[NoisePublicKey]*Peer
 	}
 
 	// unprotected / "self-synchronising resources"
@@ -129,6 +130,7 @@ func unsafeRemovePeer(device *Device, peer *Peer, key NoisePublicKey) {
 	// remove from peer map
 
 	delete(device.peers.keyMap, key)
+	device.peers.empty.Set(len(device.peers.keyMap) == 0)
 }
 
 func deviceUpdateState(device *Device) {
diff --git a/device/peer.go b/device/peer.go
index fe6de33..73e6083 100644
--- a/device/peer.go
+++ b/device/peer.go
@@ -125,6 +125,7 @@ func (device *Device) NewPeer(pk NoisePublicKey) (*Peer, error) {
 	// add
 
 	device.peers.keyMap[pk] = peer
+	device.peers.empty.Set(false)
 
 	// start peer
 
diff --git a/device/timers.go b/device/timers.go
index e94da36..dbd4c66 100644
--- a/device/timers.go
+++ b/device/timers.go
@@ -73,7 +73,7 @@ func (timer *Timer) IsPending() bool {
 }
 
 func (peer *Peer) timersActive() bool {
-	return peer.isRunning.Get() && peer.device != nil && peer.device.isUp.Get() && len(peer.device.peers.keyMap) > 0
+	return peer.isRunning.Get() && peer.device != nil && peer.device.isUp.Get() && !peer.device.peers.empty.Get()
 }
 
 func expiredRetransmitHandshake(peer *Peer) {