It could be the input drive bearings going out. I would suggest removing the back side covers of the unit and inspecting the drive assembly when its in use. Watch for deviations in the the circular motion of the crank arms. If it moves side to side or drops in the rotation its time to have the input replaced.
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It could be the input drive bearings going out. I would suggest removing the back side covers of the unit and inspecting the drive assembly when its in use. Watch for deviations in the the circular motion of the crank arms. If it moves side to side or drops in the rotation its time to have the input replaced.