Slic3r prints infill sag

I'm having a horrific time getting Slic3r to produce a print without a sagging/droopy infill. I've tried printing slower, faster, raising and lowering my extrusion multiplier, raising and lowering the bridge flow ratio and extrusion temperature, changing my infill width. Nothing seems to really effect the print in any useful manner.

When I try the same part with Cura, it works fine, so I'm highly confident that it isn't my printer's firmware calibration or the way I'm holding my mouth or anything like that. I'd like to use Slic3r because it seems significantly more configurable, but I'm tempted just to continue for a while with Cura... I've burned somewhere close to a pound of PLA trying to get the infill problem fixed.

Any suggestions would be highly appreciated.

there is a setting in Slic3r for "infill every X layers" or similar.....set this to 1. That might do it.

might need to be in expert mode

It's always been set to 1. I've been using Cura to print and it's working fine.

1013 Wrote:
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> there is a setting in Slic3r for "infill every X
> layers" or similar.....set this to 1. That might
> do it.
>
> might need to be in expert mode