Hi everyone. I own a KNC ONE DVB Plus with a Cineview module (Alphacrypt Light). From the beginning I ran into data corruption problems with the mpeg stream as soon as I made the usual X <-> VT switch or put some load on the Athlon64 3500+ machine with its RAID 5 (3 SATA disks). After some looking around, I soon discovered it was related to a buffer underrun because the following showed up in my logs every time a corruption occurred: saa7146 (0) vpeirq: used 1 times >80% of buffer (65612 bytes now) I searched the mailing list archives and learned this problem had been reported earlier and that I should increase the DMA buffer size- which I did. Running now at the maximum of 1410kb, things have pretty much been fixed. I can put load on the machine, do random X <-> VT switches and everything works most of the time. But there still is the occasional underrun even though the machine is not under load. For example, I am running mythtv on my box for scheduling recordings. From time to time, I get 3-4 underrun msgs in a short time (a matter of minutes), even though nothing is recording and the machine is far from being loaded. I don't know what mythtvbackend is doing then (maybe checking for EPG updates from time to time). Here the relevant parts of my log when the dvb modules are being loaded: Oct 14 09:19:22 saa7146: found saa7146 @ mem ffffc20000014000 (revision 1, irq 66) (0x1894,0x0021). Oct 14 09:19:22 saa7146 (0): dma buffer size 1443840 Oct 14 09:19:22 DVB: registering new adapter (KNC1 DVB-C Plus). Oct 14 09:19:22 adapter failed MAC signature check Oct 14 09:19:22 encoded MAC from EEPROM was ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff Oct 14 09:19:22 saa7146_vv: saa7146 (0): registered device video0 [v4l2] Oct 14 09:19:22 KNC1-0: MAC addr = 00:09:d6:6d:61:b5 Oct 14 09:19:22 DVB: registering frontend 0 (Philips TDA10021 DVB-C)... Oct 14 09:19:22 budget-av: ci interface initialised. Oct 14 09:19:22 budget-av: cam inserted A Oct 14 09:19:22 dvb_ca adapter 0: DVB CAM detected and initialised successfully Oct 14 09:19:22 saa7146: register extension 'budget_ci dvb'. Oct 14 09:19:35 budget-av: cam inserted A Oct 14 09:19:36 dvb_ca adapter 0: DVB CAM detected and initialised successfully If there is anything I can do to help fix or investigate this, please let me know. I am more than willing to help... Have a nice weekend and thanks for any help in advance, matthew. _______________________________________________ linux-dvb mailing list linux-dvb@xxxxxxxxxxx http://www.linuxtv.org/cgi-bin/mailman/listinfo/linux-dvb
