Ginger bug causing a gelatinous soda

I have been making ginger soda. But after fermenting, the soda was very viscous and slimy in some of the batches. It usually turns out fine but this happened multiple times inconsistently with different starts. Does anybody know what may be causing this?

Recipe used: Ginger Bug (ginger, sugar, and water) Strong ginger tea dilute with water and add sugar to 6-7 brix sweetness

i usually ferment until ~5 brix before putting in the fridge.

so really the only things in this are ginger, sugar and water, plus whatever bugs might be on the ginger skin.

the first time i thought it might be a contamination so i made a new ginger bug start. i've also moved since then with another new start. but unless i'm contaminating it in the same way every time in different environments, i don't know how i'm getting the same gelatinous consistency, so i think it might be specific to the bug?

i do make sourdough as well, but not usually at the same time, and i don't have any other ferments in the house.