Just had the same problem with the SR5E error 10/70 went back to the people who upgraded it and they say it's a bar rest software issue,only one set of coins can be registers on the coin mechanism so I have had all the old pounds 10ps removed and upgraded to new and it works perfectly.
It worked fine then I removed the hopper and that's when the issue started,I have j u st had all my coin techs updated and this is the only machine with issues.