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I had a problem for years with my otherwise excellent line losing sync in wet and/or windy weather. I am with one of the better ISPs who did their very best to get it fixed but everytime OR checked the line they found nothing wrong. On my most recent attempt to get a fix the OR engineer said he thought there was a fault on the line and it should probably be replaced, only to hear from OR via my ISP that there was nothing wrong - again.
So, feeling very frustrated and having just about exhausted all the usual options, late on the Friday I sent a polite e-mail to the CEO of OR explaining the situation and had a reply less than two hours later from one of his assistants who said he had passed the e-mail over to the relevant area engineer who would be in touch. Saturday morning I had an e-mail from the area engineer to tell me they were looking into it further and on Monday morning two very nice OR engineers turned up and replaced the entire overhead line back to where it went underground.
Since then my line has been rock solid despite what mother nature cares to throw at it.
I also had a follow up phone call from the area engineer making sure everything was OK and he also gave me his direct phone number in case there were any problems.
I should add that I have tried approaching the CEO of various organisations over the years and without fail action has been taken but I wouldn't do this until I had tried normal channels.