We know this too, I don't have a conclusive answer and can only report from our experience. We use the device with these electrodes on my wife. She feels the electrodes most unpleasantly when she has severe tension. She has this mainly on the right side of her back (bad posture) and it is so strong that she gets numbness in her arm. On the left side of her back she feels almost nothing during the treatment (at least most of the time). Even when I change the electrodes from left to right, the unpleasant feeling remains on the right side. So I assumed that it was the treatment itself. I assume that the effect is increased when there is a lot of tension and that the current works most there, which can be noticeably unpleasant. We are therefore adjusting the intensity on the one hand and the duration (less than 20 minutes) of the treatment on the other. If we use the device diligently (once a day), we notice that the unpleasant feeling becomes weaker and the intensity as well as the duration can be increased continuously. However, it has also happened that the unpleasant feeling is suddenly noticeable on the left (supposedly healthy) side. These areas then become noticeably warm (from the inside) for my wife. Reddening could also come from the glue to which the skin reacts. Changes in perception could probably also have something to do with the situation during the day (have I just showered or has the skin formed a natural layer of oil during the day, or do I still have lotion residue on the skin). At best, I would try to always clean the areas before the treatment and then dry them really well. I like the suggestion to reposition the electrodes. We usually place the electrodes directly on the problem area. I can say with certainty that my wife has almost no problems with her tension since using this device. We then discontinue the treatment each time. As soon as the problem occurs again, it can be remedied with just a few treatments.

I know that too. Often it helps to position the electrode a little differently... But that doesn't always work. I would also be interested in a solution.