I thought I’d describe what can happen with DIY if you don’t know what you’re doing backward and forwards. And it might help out anyone else with M&RIE receivers out of a similar predicament.
First, with my moderately severe high-frequency loss and NAL-NL2 as my fitting algorithm, I’m near the limit of using M&RIE receivers without getting feedback. To avoid feedback, I wear occlusive molds with no vent (and I do that also for the best noise control and beam-forming in very noisy situations).
When I get fit at my audi’s I’m in a carpeted environment, probably with sound-absorbing tiles in the ceiling, etc. At home, there are lots of bare wood cabinetry, Formica countertops in the kitchen, and bare tile floors, very reflective surfaces that help cause feedback if my fit is not right.
After the latest fit by the audi, I came home and thought, “I want to save her settings and be able to check them out myself.” So, I read the Omnia 962 settings with Smart Fit. I wasn’t going to change a single thing. But I examined options in a dropdown or two, being careful to have each dropdown back on the audi’s choice. When I went to exit the program, since I thought I’d changed nothing, I didn’t think the program would overwrite the hearing aid settings. But quite possibly, fiddling with the dropdowns made Smart Fit think the fitting had been updated, and it overwrote my hearing aid settings with the program content. I remember thinking that I hadn’t run a feedback test with the HA fittings loaded into my copy of the program; I wonder if that makes a difference? I had presumed when I’d loaded data from the HA’s into Smart Fitting that feedback information from the audi’s fit had come along. (another corollary problem might be that I have no idea whether the audi and I are running the same version of Smart Fit).
Shortly after that, I began to have M&RIE feedback problems in my right ear. I’d had that previously with the first mold made for my left ear. It didn’t occur to me that my fiddling around with Smart Fit might have anything to do with my annoying problem. I thought, Dang, it’s hard to get the mold in right. Had the wife, an M.D., look into my ear canal with an otoscope (as she’s done many times before). She said the left canal was fine, but the right looked swollen, and maybe I shouldn’t wear my right HA for a few days to let the ear canal recover. That seemed to make sense. I’d been fiddling with the right mold a lot, trying to get it in just right. That had probably irritated the ear canal. The mold had fit so well before, but now I couldn’t stop the feedback.
A few days later. The right canal looked much better. Feedback was a lot less, but still there. So, then my fleeting thought as I had exited Smart Fit came back to me. Maybe the fact that I never ran the feedback management test before Smart Fit overwrote my HA settings is what did me in. Perhaps the audi’s settings weren’t imported from the HA’s for some reason, or our versions of Smart Fit were very different?
At any rate, after loading up my fit again in Smart Fit, running feedback management, and saving the settings again with only that change, no feedback in either ear, and everything sounds great (knock on wood).
For anyone like me who suddenly develops a feedback problem with the M&RIE receivers, I discovered an interim solution is simply to switch to the Front Focus program (the Ultrafocus program might do the same for ReSound One or Jabra Enhance Pro users). In the Front Focus/Ultrafocus program, the M&RIE receivers are cut out. Only the HA body mics are active, and sound leakage from your ear canals causes a lot less or no feedback. In the focused environment, what’s in front of you does sound much louder than what’s around you but at least in a quiet to moderate environment, I could hear everything quite well and had NO FEEDBACK.
Another “solution” that I was considering if redoing feedback management hadn’t worked was switching from NAL-NL2 to ReSound’s proprietary Audiogram+ fitting algorithm based on the original NAL algorithm. Audiogram+ amplifies high frequencies much less than NAL-NL2 does, and when I was originally worried about how well my molds fit, the audi asked why I didn’t just go with Audiogram+ as ReSound had designed use of M&RIE receivers around that fit.
