Omega Speedsonic 188.0002 running fast

I recently acquired a Speedsonic a couple of months ago and it kept perfect time at the start, but recently (last week) has started running increasingly fast. First I noticed it had jumped ahead 5 minutes overnight, reset and it was fine for a day or two, then I noticed it had jumped ahead again. Then, over the last couple of days, it has started running faster and faster, to where it is now gaining around 5 seconds a minute! Any ideas on what's going on here? I also have a Longines Ultronic which has the same movement and keeps near perfect time (relative to my Bulova Lunar Pilot which is +- a few seconds a year). It has a lazy day wheel as well that sometimes doesn't snap all the way to the next day until noon, so my guess is it's just overdue for a service, but wanted to see if there was anything obvious to check - and where the current best place to have it properly serviced and repaired is.

Nobody?

hi. i,m no expert. but it sounds like one of the gears maybe worn. but you will need expert advice

Believe this is based on the f300 tuning fork movement, It would most likely be caused by the pawls/gear needing maintenance. It will need a service with omega/specialist.

Does it stop humming?

Just wondering how this is going ... ?

If you’re UK or EU based then this guy is the main specialist for these types of watches I believe:
https://electric-watches.co.uk/contact-me/