I find that my Trax 42s are getting interference whenever I walk under a motion detector. I work in a building that uses them to control the lights. I also noticed this problem in my physician’s office building. Has anyone else encountered this problem?
Hi! I was inside a car and I unnoticed activate the alarm system (I think it is a infra red motion detector) and I coul hear it in my HAs. It was very very annoying. It is what you are talking about?
Mine happens when I walk under a motion detector. They may use infrared.
It turns out that these are ultrasonic occupancy detectors and are known to cause interference with hearing aids.
A tinfoil hat might make a decent Faraday Cage. Of course, that might make patients nervous. 
I encounter this whenever I am in the administrative area of my workplace. The ceilings are lower in there, about 8 foot, which puts the motion detectors close enough to cause a problem. My HIS said it had something to do with Bluetooth, but I don’t think I buy that. I don’t go in that area too frequently, so I have just accepted it. If I had to work in that area every day, something would have to change.
I work in a number of buildings all with motion detectors. We just completed renovation of a building with motion detectors and the new motion detectors do cause interference in my hearing aids.
I think that the HAs can be programmed to a different frequency by your tech. Not sure how much frequency range they have, or whether it would make any difference in your case.
Find out the brand/model of the units and complain to the FCC. The unit are supposed to work only at a given frequency that is beyond our hearing and not cause problems for other devices. FCC inspectors are active in this area.
I reached out to the manufacturer of the Occupancy detector. They sent me a White Paper with the following language:
WattStopper, the Hearing Industries Association, and
a leading manufacturer of hearing devices, have been
working together to gain a better understanding of what is
happening in cases of interference and what can be done
to prevent interference from occurring. The long term
solution however, is for the hearing device manufacturers
to address the device design. Resound Corporation, one
of the largest manufacturers of personal hearing systems
in the United States, recently introduced the first of a
new line of hearing devices that are immune to ultrasonic
interference. These hearing devices are based on a new
design which can account for sound emitted from other
sources while maintaining the high quality of audible
sound mandatory in Resound Corporation products. The
competitive nature of the hearing aid device industry is
prompting other manufacturers to develop similar designs
that compensate for the increasingly common problem of
interference from sound emitting devices.
The cause of personal hearing device interference,
in most cases, occurs when a hearing aid device is
operating outside its designed specification. Because
the interference phenomenon can be seen with not only
ultrasonic occupancy sensors but also with other more
common sources such as automatic door openers,
electronic ballasts, and cordless phones, it is important
that the user of the hearing aid device contact the
manufacturer or supplier to have the aid adjusted or
replaced.
Ah… good to know that it is everyone’s fault – except the manufacturer of the device that is emitting unwanted ultrasonic radiation. And AFAIK Resound is a Danish company.
I wonder what these things do to dogs. They probably CAUSE hearing loss.
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My first set of hearing aids were Sonic Innovations and I could be on the road back then and I could hear a buzz in my hearing aids then the next thing I would notice would be a policeman that was running radar on the roads. That was about 11 years ago and I never figured out if it was the hearing aids are the radar. I have never found that true with any of the other hearing aids that I have had or have.
When GSM/DECT phones first started to give issues in the 0.8/0.9MHz range, there were specific interference problems which sounded like a motorboat engine. You can still hear them if you put your cell phone near your car radio.
Mic designs were modified to introduce grounding across the halves of the mic case and contact the ground 0v terminal.
Before 1990s mics used in hearing aids have had ultrasound capability. The FG series had a flattish response up to 20kHZ and even had a resonance peak around there. It would seem to be a fairly simple move to cut the bandwidth down on the modern hearing aids as there’s clearly no speech information out there.
The problem is that manufacturers read this board and it would appear that there’s a couple of posters who are championing wider band hearing aids as ‘the answer’ when clearly they aren’t. Unfortunately due to the effect of numbers on Engineers and the uninformed it’s likely that broader band hearing aids with Frequency lowering are going to become more the norm. This type of interference is likely to become more common.
I work for a large employer. At one of my last job stations, they had installed motion controlled, high efficiency fluorescent lighting. Whenever I was in close proximity to the ceiling mounted sensors, I would get a whine in my Phonak aids that varied with the distance and/or angle. I had to have them install a different wall sensor built into the old switch plate. It was IR rather than ultrasound and didn’t cause the problem. Obviously, they disconnected the ceiling sensor in my office. Thank goodness for the reasonable accommodation process.
Jeff
The Rexton Audiologist told me that this was a function of all new hearing aids. I do not know if I am going to bite on that. She said it is because the motion detectors are on frequencies close to the ones the hearing aids use to communicate with each other. She tried changing the channel. But it didn’t make a difference.
I’ve been noticing this as well. It’s been infrequent (fortunately). I was glad to see your post - was wondering what is going on. I was at a hotel a few weeks ago and every time I used the stairwell, I noticed interference near the doorways.
I recall that electronics are all tested and rated for radio frequency radiation. Are there no regulations for ultra-sonic radiation? What’s wrong with the old IR sensors? Ultra-sonic radiation has been studied in many contexts and found to have negative impact on wildlife, from bats to whales.
After a half dozen-ish tweaks to my Trax 42 hearing aids, I am still getting interference from the motion detectors. I was able to get a pair of Bernafons for testing. They are not getting the interference. I spoke to the chief electrician for our university. He reached out to the occupancy detector manufacturer. They seemed to begrudgingly acknowledge the problem and state that they have no fix for it. So, I will be returning my Trax 42s and getting the Bernafons.
I noticed a chattering (Like chipmunks whispering sweet nothings in my ear) when I walk under the one in my work’s restroom - I think that’s a dual mode sensor. the one in my office (IR only) has no effect. It doesn’t bother me, but then again, if the dual mode sensors were everywhere, I would probably go insane.
Chattering like chipmunks is an excellent description. The Trax 42s go back today and I will order the Bernafons and should have them next week. I am back to wearing my original Unitron hearing aids in the interim. I am not sure that the Trax 42s were substantially better than my four year old Unitron Moxis. In addition, the lispy sound that many of my colleagues had with the Trax is now gone, as is the occasional chirping. Although, these last two problems may have been resolvable with molded domes. Oddly, my Unitrons have a closed dome on the right and an open dome on the left and I never had the chirping or lisping problem with them.
Bob