Repeater trouble

[hyla]

Hi,

looking into the problem with my just occasionally working repeaters. Using Yveaux' sniffer I find that my repeater (13)keeps asking for a parent:
13 255 mysensors 17 Cmd:INTERNAL, ReqAck:0, IsAck:0, Type:FIND_PARENT, Sns:255

Occasionally this is answered:
0 13 mysensors 18 Cmd:INTERNAL, ReqAck:0, IsAck:0, Type:FIND_PARENT_RESPONSE, Sns:255, Data:0 [BYTE]

Nevertheless, repeater node 13 keeps asking ...

An idea anyone? Repeater asks for parent, is answered but keeps asking?

Thanks for any help,
Christoph