The Feed Tubes can vibrate back into the case a small distance
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I recently received an e-mail from an owner with an interesting problem. Apparently the reservoir feed tubes tubes can actually vibrate back slightly into the body of the machine, this means they are up further from the bottom of the tank and may suck dry before the low water level indicator goes off.
This is a relatively easy fix and made by simply placing a cable tie at the point indicated, ensuring that the free end is not cut too short. It's important to ensure the cable ties is tight enough to not slip, but not so tight that it restricts water flow. I would imagine this modification would be worthwhile on most/all Expobar home use espresso machines.

Izzo have been doing it for years, although they have cut the free end quite short as you can see, for the Expobar I recommend leaving a 1cm tag on the cable tie.