I just serviced my regulators, the second stages are Aqualung legend unadjustable=titan LX supreme.
They are very similar to apeks xtx.
They have no issue under water, but while breathing in moderately on land, 1½ of my 4 2nd stages make a humming action/sound. The whole membrane system resonates a bit.
I've double-checked the adjustments, lever heigth and opening effort is right. The membranes look like from the same generation.
In the service manual, it is stated that you should confirm that it doesn't make any humming (stuttering is the wording), if it does, check the troubleshooting table - but it is not mentioned there..
As mentioned, it doesn't happen in the water, so maybe I'm just over-caughtious.
They are very similar to apeks xtx.
They have no issue under water, but while breathing in moderately on land, 1½ of my 4 2nd stages make a humming action/sound. The whole membrane system resonates a bit.
I've double-checked the adjustments, lever heigth and opening effort is right. The membranes look like from the same generation.
In the service manual, it is stated that you should confirm that it doesn't make any humming (stuttering is the wording), if it does, check the troubleshooting table - but it is not mentioned there..
As mentioned, it doesn't happen in the water, so maybe I'm just over-caughtious.