[UPDATED BELOW, 9/25] Negotiations resumed this afternoon between Chicago Symphony Orchestra management and the Chicago Federation of Musicians, local 10-208, which represents its players.

The musicians went out on strike last Saturday, about an hour before a scheduled concert at Symphony Center.

The musicians’ contract expired September 16, but they were continuing to play during negotiations. According to a statement on their Facebook page, when management presented them with a contract that “represented an increase of only $20 over the contract term” [three years] from the previous offer, they “concluded that management was not negotiating in good faith and felt compelled to call a work stoppage.”

The timing was unfortunate; many patrons had already set out for the concert.

The main issues are compensation and health insurance costs. Minimum pay for orchestra members under their previous contract is $144,820. Management offered a $10 a week raise in the first year (with only slightly larger increases in the following two years), and wanted musicians to increase their share of health insurance costs.

The musicians say their total compensation would then be less than the “current top-paid U.S. orchestra,” which would compromise the CSO’s competitive edge.

It’s risky business: the orchestra has high-profile dates ahead, including a Carnegie Hall visit that starts October 3.

UPDATE: This message was posted last night (9/24) by CSO management:

The musicians and management of the Chicago Symphony Orchestra have arrived at a tentative agreement for a new, three-year collective bargaining agreement. Ratification of this new contract is still pending by both parties—the Chicago Federation of Musicians and the CSOA Board of Trustees—at which time further details will be announced. When ratified, the new contract will take effect retroactively on Monday, September 17, 2012.

All previously-scheduled CSO activities will proceed as planned.