--- linux-2.6.23.12/sound/pci/es1938.c.trydma	2008-01-14 23:46:57.000000000 +0100
+++ linux-2.6.23.12/sound/pci/es1938.c	2008-01-23 01:03:08.000000000 +0100
@@ -227,6 +227,8 @@
 	unsigned int dma2_start;
 	unsigned int dma1_shift;
 	unsigned int dma2_shift;
+        void*        last_capture_dmaaddr;
+
 	unsigned int active;
 
 	spinlock_t reg_lock;
@@ -775,14 +777,38 @@
 	struct es1938 *chip = snd_pcm_substream_chip(substream);
 	size_t ptr;
 	size_t old, new;
-#if 1
+#if 0
 	/* This stuff is *needed*, don't ask why - AB */
 	old = inw(SLDM_REG(chip, DMACOUNT));
 	while ((new = inw(SLDM_REG(chip, DMACOUNT))) != old)
 		old = new;
 	ptr = chip->dma1_size - 1 - new;
 #else
-	ptr = inl(SLDM_REG(chip, DMAADDR)) - chip->dma1_start;
+	/* during the incrementing of dma counters the DMA register reads sometimes returns garbage.
+	   To ensure a valid hw pointer, the following checks which should be
+	   very unlikely to fail are used:
+	   - is the current DMA address in the valid DMA range ?
+	   - is the sum of DMA address and DMA counter pointing to the last DMA byte ?
+	     One can argue this could differ by one byte depending on which register is
+	     updated first, so the implemention below allows for that.
+	*/
+	size_t stat,count;
+	unsigned int diff;
+	struct snd_pcm_runtime *runtime;
+	runtime = substream->runtime;
+	ptr = inl(SLDM_REG(chip, DMAADDR));
+	count= inw(SLDM_REG(chip, DMACOUNT));
+	diff=chip->dma1_start+chip->dma1_size-ptr-count;
+
+	/*	    printk("Es1938debug - capture_pointer %x,diff=%x,fb=%x DMA count: %x, base: %x, status: %x\n",
+		       ptr,diff,((unsigned char*)(runtime->dma_area)-1)[0],count, inl(SLDM_REG(chip, DMAADDR)), inl(SLDM_REG(chip, DMASTATUS)));
+	*/
+	if (diff>3 || ptr < chip->dma1_start
+	      || ptr >= chip->dma1_start+chip->dma1_size)
+	  ptr=chip->last_capture_dmaaddr;                 /* bad, use last saved instead */
+	else chip->last_capture_dmaaddr=ptr;              /* good, remember it */
+
+	ptr -= chip->dma1_start;
 #endif
 	return ptr >> chip->dma1_shift;
 }