MkV Gti - headlamp washers

[MBradbury]

When using the windscreen washers at night (ie when the xenons are on), the headlamp washers come on every time. This is a bit of a pain and drains the washer bottle very quickly, can this be changed? I had my car in for a service a week ago but the VW dealer said there is not way of changing this, not sure if I believe them - more likely couldn't be arsed to try.

Any thoughts if this can be changed?