My PSTN line unable to drop calls completely

Hello All,

I am running AsteriskNow 1.7.1 + FreePBX (2.7.0.10), DM400A (2FX0+2FXS), please help my AsteriskNow box unable to drop PSTN line completely …

I tried to put

busydetect=yes
busycount=6

to chan_dahdi.conf … but it does not work, I have to always restart my AsteriskNow box to make my PSTN line available.

please help

Thanks & Regards

i think it is a problem with hardware, please show dmesg message.