Need help changing from 5060 to 5160

Newbie is as Newbie does.

I need a bit (read: a lot) of hand holding. I’m traveling in a foreign country and am having problems with calls dropping after 20-30 seconds. Using a Raspberry, Flowroute and SPA504G. From what I’ve read, I need to change port 5060 to 5160.

According to the post: “SIP ALG often times is introduced when ISP’s upgrade some equipment and in these cases they can malform SIP packets. When the packets are malformed, they are not sent/received correctly causing the issue you are experiencing. Using the alternate port 5160 bypasses the ALG and allows for normal call setup.”

My questions are: where/how do I need to change from 5060 to 5160 in freepbx and the spa504g. Is there anything that needs to change at flowroute?

Would love to get the raspberry working with the spa504g on flowroute and not get dropped after 20 seconds.

Thanks so much.
MegaNewbie Howard.