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Tips and Troubleshooting
Your ds32a+ is designed, built and tested to provide you with excellent sound quality and performance. If you have any questions, comments, suggestions or experiences you would like to share, please let us know at
We will respond to all emails. If you have a problem requiring more immediate attention, please call us.
Before contacting us, we suggest that you read relevant sections of the User’s Manual, read this section of tips and troubleshooting suggestions, and look at www.thinklabsmedical.com, where we will place FAQ’s, updates and useful information for Rhythm owners.
Get the most out of your ds32a+ - Most users do not read User’s Manuals. We have tried to provide additional information and tips in the Manual to help you get the most out of using the ds32a+. In particular, read the following sections:
Optimal Use of the ds32a+
Volume Settings and Psychoacoustics
Auscultation - a Pathology-Physiology Dichotomy
Noise Rejection (NR)
Listening with the ds32a+
The ds32a+ does not Turn On
- Check the Battery polarity. The wrong polarity can cause damage to the ds32a+.
- Batteries may need replacement. Follow instructions here.
The ds32a+ is not producing any sound
- No sound in Amplify mode (when Blue LED On). Increase the Volume setting. It may be set at a very low level. Set Volume to say, ‘7’, and try again.
- Check the headphone fit. Do you have the ds32a+ on backwards and the eartips are facing the wrong way? The eartips should face forward, and the control panel should face forward. Check the adjustment of the eartips..
The ds32a+ is producing unexpected interference or noise
The ds32a+ should provide a low-noise, high-quality signal. If used on clothing or not applied correctly to the patient, artifact can be produced. Simply apply the Probe as recommended, making good contact with the patient. There are some interfering noises that can occur even when not examining a patient.
Some potential culprits are listed below, with remedies:
- Radio stations or electromagnetic pickup: Move the ds32a+ to a location that does not have strong electromagnetic fields from such sources.
- Continuous loud buzzing: The diaphragm is loose. Tighten the diaphragm retainer ring.
- Continuous loud buzzing: The ds32a+ is connected to mains-powered or grounded equipment. If you have the ds32a+ connected to an external device, is the device powered by mains electricity or on a wired network? If so, disconnect the other cables from the equipment, so that the ds32a+ is connected only to “floating” (ungrounded) device.
- Other noise: Dust or moisture may exist inside the Probe.
Problem unsolved? Contact Thinklabs for assistance.
Headphones do not fit correctly or are uncomfortable - Are you wearing the headphones the right way?
The eartips should face forward, and the Control Panel should face forward.
- Eartips or headphones are out of alignment .
- Headphone spring tension isn’t correct.
Sound is sometimes distorted or cuts out temporarily when listening
- Volume is too high. Reduce Volume level or try Acoustic mode.
- Excessive pressure is being applied when listening. Decrease pressure for loud sounds.
- Probe is not being held in a firm and steady position, or is not being held with a steady pressure against the patient. The ds32a+ EmD diaphragm can sense frequencies down to the sub-sonic range, in order to cover the whole audio spectrum for murmur detection. Vibrations caused by patient or user hand movement are also sometimes sensed as loud signals that distort body sounds. Hold the Probe steady with a light but consistent pressure against the patient. It sometimes helps to hold the Probe so that the fingers holding the Probe also touch the patient chest wall, so that the Probe and chest wall move in unison.
Heart sounds on some patients are difficult to hear
Heart sounds are attenuated in obese patients. When patients have substantial body hair, this reduces the contact of the diaphragm against the body. Similarly, clothing can sometimes reduce sound transmission. This is a matter of physics, and in such circumstances, conventional stethoscopes are usually not effective. To overcome such limitations, try and ensure that the EmD diaphragm is making good, direct skin contact, preferably in a location that has less body fat or hair to cause attenuation. Do not apply excessive pressure on the Probe. Preferably, apply a light but firm pressure, so that the low-frequency sensitivity of the ds32a+ is optimized, and the diaphragm is making full contact with the patient. Then gradually increase pressure to increase EmD sensitivity to quiet sounds.
Working in high ambient noise environments
Rhythm stethoscopes are designed to attenuate ambient noise. Use the Noise Rejection (NR) function to reduce ambient noise.
Other steps to further optimize listening:
- Do not listen through clothing.
- Ensure that the diaphragm is making good contact with the patient.
- Apply light but firm pressure on the Probe. Do not press too hard.
- Adjust the Volume such that body sounds are audible, but avoid using such a high volume that ambient sounds become audible. There is usually an optimal volume setting for a given environment.
- Experiment with the Acoustic Aperture. In high noise environments, it is suggested that the Aperture be kept open!