Static - PRI/T1

The two most common causes of static on a PRI/T1 are timing and echo cancellation.

For timing problems, please consider the following steps to resolution:

1. Check the physical connection - a bad cable between the smart jack and the PRI card installed in your PBXtra can introduce static to an otherwise perfect connection.  Please replace the cable.

2. Check the timing source - nearly all PRI connections should have a timing mode of NORMAL set.  To check the timing on your card:

   1. Click on Options --> cards

   2. Select your PRI card from the drop-down list above the graphic of a PCI card

   3. Click Edit from the small box next to the actual port

   4. Under Port X Settings (where X is the Port number), the option Timing should be set to 'yes'.

   5. Click on [ Advanced Mode ] at the top

   6. Click the + sign next to the word 'Wanpipe'

   7. Within the window, scroll down until you see this line:  TE_CLOCK=NORMAL

   8. If the TE_CLOCK setting displays 'MASTER' and you do not have a Rhino Channel bank, please erase 'MASTER' and type in 'NORMAL' (in all caps)

   9. Click "Apply All Changes"

3. Toggle Hardware Echo Cancellation - sometimes a faulty hardware echo cancellation module can introduce static on your PRI.  It's also possible that the carrier has already eliminated all echo on the line and using the hardware echo cancellation technology actually causes echo (this is exceedingly rare however).  To turn off HWEC and test:

   1. Click on Options --> cards

   2. Select your PRI card from the drop-down list above the graphic of a PCI card

   3. Click Edit from the small box next to the actual port

   4. Click on [ Advanced Mode ] at the top

   5. Click the + sign next to the word 'Wanpipe'

   6. Scroll down to the bottom of the file and check for the following setting: TDMV_HWEC=YES

   7. Change the word YES to NO

   8. Click "Apply All Changes"

4. Please make a test call after each of the changes detailed above.  Perform all test calls from the same phone (preferably a land-line) for consistency.