I have a code 100H. When using the headphones, the effects loop does not come through. If I connect an external cabinet it works fine. Why doesn't the FX come through in headphone mode? Thank you.
I think you can restart this app first to see if that still exists. Or you can try removing the case from your device. One of the easiest ways to fix any software related issue with your iPhone is to give the device a hard reset. Or try to use the Airport mode: Go to Settings > Airplane mode and open it, or swipe up to access the Control Center and toggle it on the Airplane mode option. Then you need to wait for 15 minutes or more and turn it off to see whether the headphones sign disappears from your screen. Use some iOS repair tools likeTunesKit iOS System Recovery. It is capable of retaining all the existing data.