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Fixed phase calculation when downsampling

--- a/dumb/src/helpers/lanczos_resampler.c

+++ b/dumb/src/helpers/lanczos_resampler.c

@@ -154,6 +154,7 @@

 			// accumulate in extended precision

             double kernel[LANCZOS_WIDTH * 2], kernel_sum = 0.0;

 			int i = LANCZOS_WIDTH;

+			int phase_adj = phase * step / LANCZOS_RESOLUTION;

 			double sample;

 			if ( out >= out_end )

@@ -162,7 +163,7 @@

 			for (; i >= -LANCZOS_WIDTH + 1; --i)

 			{

 				int pos = i * step;

-				kernel_sum += kernel[i + LANCZOS_WIDTH - 1] = lanczos_lut[abs(phase - pos)];

+				kernel_sum += kernel[i + LANCZOS_WIDTH - 1] = lanczos_lut[abs(phase_adj - pos)];

 			}

 			for (sample = 0, i = 0; i < LANCZOS_WIDTH * 2; ++i)

 				sample += in[i] * kernel[i];