Original Sonic Port. Guitar in to the input jack, regular cable from the output jack to the amplifier guitar input, current version iPad with latest software. Works fine through the headphones, but not to the amp. Just plugging that same amp cord into the guitar - old school, as it were - the amp is fine.
This is an old and well used Spider, very early days when it was pretty difficult to get good tones set. Got the Sonic Port to get around having to deal with the settings on that amp, but I could just go out and get another amp if necessary. I don't understand why this isn't working, though, must admit.
Thanks for the response!