Hi siriusblack - not sure what you mean by your wifi ip address.
Normally you will have two sets of IP addresses:
- a single external address that is visible to everyone in the world. This address is assigned to you by your service provider. It is as shown by the web site http://www.whatismyip.com/ when run from your network.
- a range of internal addresses that is set by your router. These normally (but not always) look like 10.x.x.x or 192.168.x.x. These addresses are only used inside your network and are not visible or reachable from the outside world. One of these addresses will be allocated to the PC you are running Serviio on. You cannot use this address for remote access (as they are not visible outside of your home network).
You do not need to change any addresses in your router - your service provider normally gives the external address to your router (and it may change from time to time). The router looks after your internal address range (which is not relevant for the purposes of remote access), not the external one (which is what you need here - for all the IP guru's, yes I am simplifying

)
To get remote access you must use the external address from
http://www.whatismyip.com/. Further, you cannot use this address from inside your network - you must either go to someone elses house and use their network, or use your mobile phone (ensuring it is not connected to your WIFI network). Don't do it from work, as most corporates block this sort of traffic.
Hope this helps.