diff --git a/src/mame/drivers/vis.cpp b/src/mame/drivers/vis.cpp
index 0665f2549e6..728462ccb51 100644
--- a/src/mame/drivers/vis.cpp
+++ b/src/mame/drivers/vis.cpp
@@ -211,11 +211,10 @@ WRITE8_MEMBER(vis_audio_device::pcm_w)
 	}
 	if((m_mode & 0x10) && (m_mode ^ oldmode))
 	{
-		const int rates[] = {44100, 22050, 11025, 5512};
 		m_samples = 0;
 		m_sample_byte = 0;
 		m_isa->drq7_w(ASSERT_LINE);
-		attotime rate = attotime::from_hz(rates[(m_mode >> 5) & 3]);
+		attotime rate = attotime::from_ticks((double)(1 << ((m_mode >> 5) & 3)), 44100.0); // TODO : Unknown clock
 		m_pcm->adjust(rate, 0, rate);
 	}
 	else if(!(m_mode & 0x10))