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New Member

Phones drops calls and ringing thru issues on UC520

I have a UC520 with six(6) PSTN lines in rotary connected to FXO cards. I am having an issue with calls being dropped, ringing and no one on the line and transfer problems. All six (6) numbers appear on all four (4) 7931 phones. Can anyone tell me why this may be happening?

Hall of Fame Super Gold

Re: Phones drops calls and ringing thru issues on UC520

Which exact IOS are you using (complete output of "show version") ?

New Member

Re: Phones drops calls and ringing thru issues on UC520

Cisco IOS Software, UC500 Software (UC500-ADVIPSERVICESK9-M), Version 12.4(11)XW4, RELEASE SOFTWARE (fc3)

Technical Support:

Copyright (c) 1986-2007 by Cisco Systems, Inc.

Compiled Thu 27-Sep-07 19:25 by prod_rel_team

ROM: System Bootstrap, Version 12.4(11r)XW, RELEASE SOFTWARE (fc1)

Tony_Liker uptime is 11 weeks, 1 day, 7 hours, 1 minute

System returned to ROM by power-on

System restarted at 14:50:03 GMT Tue Mar 18 2008

System image file is "flash:uc500-advipservicesk9-mz.124-11.XW4"

This product contains cryptographic features and is subject to United

States and local country laws governing import, export, transfer and

use. Delivery of Cisco cryptographic products does not imply

third-party authority to import, export, distribute or use encryption.

Importers, exporters, distributors and users are responsible for

compliance with U.S. and local country laws. By using this product you

agree to comply with applicable laws and regulations. If you are unable

to comply with U.S. and local laws, return this product immediately.

A summary of U.S. laws governing Cisco cryptographic products may be found at:

If you require further assistance please contact us by sending email to

Cisco UC520-8U-4FXO-K9 (MPC8358) processor (revision 0x202) with 249856K/12288K bytes of memory.

Processor board ID FTX1144Y184

MPC8358 CPU Rev: Part Number 0x804A, Revision ID 0x20

10 FastEthernet interfaces

2 terminal lines

6 Voice FXO interfaces

4 Voice FXS interfaces

1 Voice MoH interface

1 cisco service engine(s)

128K bytes of non-volatile configuration memory.

125440K bytes of ATA CompactFlash (Read/Write)

Configuration register is 0x2102

Hall of Fame Super Gold

Re: Phones drops calls and ringing thru issues on UC520

Hi, can you please upgrade to 2.4(11)XW8, the one you're using has many many bugs.

Hope this helps, please rate post if it does!