Finally I found a post to make about voice! I am sure we have all been in the situation where we have had to take ISDN channels out of service to help diagnose a problem (Some customers for example, seem to have one way voice issues on single channels, or other such problems) and it is helpful when you can confirm what the heck the issue is by taking out an ISDN channel, or just as a quick stop gap measure while you wait for new DSP's or the telco to fix the issue
Here is how to do it on an E1:
Router(config)#interface serial 0:15
Router(config-if)#isdn service b_channel X state 2I found this at:
This works for SIP and H.323 gateways, for MGCP you need to set the enterprise parameter.