If you hear a cracking noise from your transducers, follow the steps below to troubleshoot the issue.
Check the transducer for physical damage, such as cuts on the cable or audio jack.
Unplug the transducer, plug it back in, and gently wiggle the cord into the audio jack before testing again.
Try plugging the transducer into another device, such as a cell phone, and check if the crackling occurs.
Try plugging a different transducer into the iPad (such as a pair of earbuds) and check to see if the crackling occurs while using those (this could indicate an issue with the iPad's audio jack).
If the crackling noise persists, contact support.