[avahi] PTR query responses

[Markus Rathgeb]

Hello!
I have here multiple machines with the same setup.
Normally if a multicast question for a PTR "_srv._proto.local" is
made, the machines reply with a multicast response containing four
records, the types PTR, TXT, SRV, A.
This morning I see (wireshark) a machine that reply contains only the
PTR record -- missing the TXT, SRV and A type.
If a multicast question for the A record of the machine's name is
requested, the machine answered with a multicast respone given the A
record.
After a restart of the avahi daemon of this machine, the machine's
reply to the PTR question contains all four records (PTR, TXT, SRV, A)
again.
What's going on?
Could someone explain me, how I could run in that situation and
whether it is correct or not (why)?
Thanks in advance,
Markus