diff --git a/CHANGES b/CHANGES
index e32b2293f..8374dc510 100644
--- a/CHANGES
+++ b/CHANGES
@@ -23,6 +23,7 @@ Emulation fixes:
  - GBA SIO: Fix Normal mode being totally broken (fixes mgba.io/i/1800)
  - GBA Video: Latch scanline at end of Hblank (fixes mgba.io/i/1319)
  - GBA Video: Fix Hblank timing
+ - GBA Video: Invalidate map cache when modifying BGCNT (fixes mgba.io/i/1846)
  - SM83: Emulate HALT bug
 Other fixes:
  - 3DS: Redo video sync to be more precise
diff --git a/cinema/gba/bg/ff6-midframe-update/baseline_0000.png b/cinema/gba/bg/ff6-midframe-update/baseline_0000.png
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diff --git a/cinema/gba/bg/ff6-midframe-update/baseline_0001.png b/cinema/gba/bg/ff6-midframe-update/baseline_0001.png
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diff --git a/cinema/gba/bg/ff6-midframe-update/baseline_0002.png b/cinema/gba/bg/ff6-midframe-update/baseline_0002.png
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diff --git a/cinema/gba/bg/ff6-midframe-update/test.mvl b/cinema/gba/bg/ff6-midframe-update/test.mvl
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index 000000000..9bb96c645
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diff --git a/src/gba/renderers/video-software.c b/src/gba/renderers/video-software.c
index de0a2279b..20783292d 100644
--- a/src/gba/renderers/video-software.c
+++ b/src/gba/renderers/video-software.c
@@ -760,6 +760,7 @@ static void GBAVideoSoftwareRendererWriteBGCNT(struct GBAVideoSoftwareRenderer*
 	bg->screenBase = GBARegisterBGCNTGetScreenBase(value) << 11;
 	bg->overflow = GBARegisterBGCNTGetOverflow(value);
 	bg->size = GBARegisterBGCNTGetSize(value);
+	bg->yCache = -1;
 }
 
 static void GBAVideoSoftwareRendererWriteBGX_LO(struct GBAVideoSoftwareBackground* bg, uint16_t value) {