Problems with SIP mikrotik oktell, what to do?

Question

SIP

Good day everyone!!!
I have a terrible problem, I'm already tired...
I have:
A provider with a static ip address. (Router mikrotik) There is a telephony server based on Oktell
In the office, telephony works beautifully, there are no problems !!!
There is a recreation center:
There the Internet mobile (MODEM)
(Router mikrotik)
is up between them, VPN with ipsek
RDP, Fiscalniks everything works fine at local addresses.
Telephony is also configured at the local address:
And it is not audible, then on the one hand, then on the other.
Grave silence, the last time it helped me, that's the rule....
/ip firewall filter add action=accept chain=forward dst-address=192.168.1.32 dst-port=5060,10000-20000 protocol=udp in-interface=wan
/ip firewall nat add action=dst-nat chain=dstnat dst- port=5060,10000-20000 in-interface=wan protocol=udp to-addresses=192.168.1.32
I wrote this from both sides, from both routers.
it worked for a day and it broke.
If all routers turn off for 10-20 minutes, it seems to work a little and break, in the router I'm not an expert, help me with good advice or for money please!

Answer 1

I hope SIP ALG is disabled?

Answer 2

What type of VPN was raised?