Unfortunately, the 2414U isn't supported by the iHealth tool.
Are some of your modules working? If some are working or work some of the time, then it is a signal issue. If all of the modules stop working, then it could be a PowerLinc failure or the Venstar thermostat adapter getting into a bad state if you have one (they can get into a bad state and send endless commands). If the latter is the case, then you can reset them by unplugging the Venstar adapter card to reset it.
Note that nothing has changed in how Indigo sends/receives INSTEON commands. Signal noise can be difficult to track down and it can come from unlikely sources. For example, I've had signal problems caused by a mobile phone charger when it is plugged into a particular outlet. For troubleshooting signal problems the first thing we recommend is FilterLincs on any UPSs, and then moving AccessPoint RFs (or other dual-band modules) to different outlets. That will change up the signal path and might help.