As I indicated "Best Config".... If I set the clock on the Point to Point Circuit in Site 1 to Internal the circuit goes in up/down state at site 1 and down/down in site 2. Here is that config:

Site 1:

network-clock-participate wic 0
no network-clock-participate wic 1
network-clock-select 1 E1 0/0/0

controller E1 0/0/0
line-termination 75-ohm
channel-group 0 timeslots 1-31
!
controller E1 0/1/0
clock source internal
line-termination 75-ohm
channel-group 0 timeslots 1-31

!

interface Serial0/1/0:0
ip address 172.16.10.9 255.255.255.252
encapsulation ppp

Site 2:

network-clock-participate wic 0
network-clock-select 1 E1 0/0/0

!

controller E1 0/0/0
line-termination 75-ohm
channel-group 0 timeslots 1-31
!

interface Serial0/0/0:0
ip address 172.16.10.10 255.255.255.252
encapsulation ppp

That kind of negates the claim by SP that they do not provide clock.

Note, not only is rare that no clock is provided on E1 circuits, but often SP answer from the first line of support without really knowing what they are talking about.

I think the errors on the circuit can be due not to clocking problem but faulty circuit, in that case you have to insist with SP even if they claim everything is OK. You can ask for a 48-hours BER test, make sure you are present in person to observe the way is conducted and the results.

So then your suggestion is to leave the config as defined in my first post? I have had the provider test this circuit several times... they insist the problem is with my equipment and suggest I replace the VWICS. It sounds to me as though I need them to remove their clocking signals from the line, is that why the circuit will not come up when the clock is set to internal?

When a circuit has problems with cisco routers, it is always the circuit fault. When that happens, you can use any clock configuration, the circuit will behave poorly anyway, as you noted. Beside, you cannot "remove" clock from a circuit, either is there, or not.

Telco will always blame the router and suggest you replace this and that, that never helped in my 20 yrs of experience in telecom, And, I never seen a faulty VWIC.

Moreover, their "test" is usually a quick one done without the customer seeing, and the firm intent to pass it and move on.

Ask for a BER test in your presence, with different test patterns. Ask the technician to show you how the test is actually done.

And stop payments until done to your satisfaction.