I wonder whether anyone has any similar experiences with a Yamaha or can offer advice.

I'll recap events below and try to keep it as brief as possible.

Sep 08 - Got rental piano in. Had for a year, no problems, stayed in tune. Position of piano up against a turned off radiator (nobody have a heart attack!) so room is quite cool now. Room quite bright but I wouldn't say piano received direct sunlight.

Sep 09 - Purchased Yamaha U1, factory fitted silent system, 11 years old, from a company who are tuner/technicians. Piano placed in same position as rental with rad off. No problems until tuning.

End Oct 09 - Contacted firm for free tuning and they recommended to use local firm to me (that they know) and for firm to bill them. Contacted local firm and requested tuning, even though I did say that I didn't feel the piano had gone out of tune.

Tuner did his job, said it was out very slightly (which I have to admit I didn't notice). A day later I noticed the piano had slightly gone out of tune in an area about 2 octaves above middle C. About 6-7 keys. It was very slight but annoying.

Contacted local firm and he was very surprised but came back and agreed it had gone out of tune. He said he didnt feel there was anything amiss with piano as he knows the dealers I bought from. He re-tuned it again for me. We discussed possible environmental factors to cause it but he did say if anything happened again to contact him.

Well again, the same thing has happened. It's in the same area of the keyboard. I really don't think it's him but then the only other option is the piano, but then how did it hold its tune for 8 weeks?

I have even spoken to a PTA examiner and he knows my tuner and didn't think he himself (the examiner) would do any better a job than my tuner.

I am going to contact my tuner today to see if he can strip the piano down and check it over before going back to the dealers. My piano has a 5 year guarantee so I am praying if anything is wrong it will be covered but am starting to be worried.

Has anyone got any ideas???

Be careful before your tuner strips it down, you don't want to do anything that might invalidate the guarantee.

I've not come across this before, I'd be inclined to get in touch with the dealer first.

I Agree.

Me too. Contact your dealer.

I have a U3 Yamaha also with a silent system fitted which I bought from new about 8 years ago. When I first bought it, it took ages to settle down after it was delivered, I was having to have it tuned pretty much every 6 weeks, gradually stretching to 3 months over the first year, and it needed frequent tuning for several years after that. Admittedly this was a brand new instrument, and I see that yours is already 11 years old. Because I was concerned about it, I bought a hygrometer, a simple instrument that measures humidity, and the results were fascinating. It was only about £20 and I still use it all the time to monitor conditions in the room.

The humidity in my music room was much much drier than normal room humidity. I think ideal piano conditions are something like 45-60%. In my room with the heating on in winter, it never got above 30% and in addition to that, as the heating went on and off, there were huge temperature and humidity fluctuations which can't have helped the piano.

I then had to move house temporarily for 6 months, in the new place, the humidity was above 50% constantly, and the piano stayed in tune. Weirdly, since I moved home, it has also held its tuning better than before, although I do sometimes notice the odd note slipping soon after tuning.

I wonder if maybe your piano is still adjusting to its new surroundings after being moved. Have you put your central heating on since it was delivered? But I agree that if you are not sure, you should speak to the dealer, as if you do not notify them of your concerns immediately, your consumer rights may be affected a bit further down the line. I would also notify them before having your tuner do any additional work to it, as the previous poster is right in saying that it may invalidate the guarantee.

Oh brilliant, thank you. I'll order one asap.

I am sure it is environment that could be causing the issue, however it doesn't explain how the £800 rental wasn't affected (acquired at the same time as the Yamaha but last year), yet the Yamaha is. Plus it's wierd how it stayed in tune for 8 weeks until it was first tuned, but then as you say that was the summer and the heating was off/just being put on on the odd occasion.

Funnily enough in our dining room we have a cheapo dining table from Homebase which develops cracks in it as the wood contracts and expands. Over the summer the cracks disappear and over the winter they open out up to 2mm wide, so it shows how dry it must get in our house.

I am waiting for the tuner to call me back. He knows the dealer that I bought from so I'll speak to him before I call my dealer.

Thanks everyone. Feeling less apprehensive for now.

Our old piano had a crack or cracks in the sound board. Weirdly mainly the C's used to go out of tune. They didn't hold hardly at all. It was 50 years old and at one point in it's life had been rather close to a radiator before we got it handed down from my grandmother. The piano tuner said it might be possibble to bolt anothe board onto the original one , but that it would be rather experimental! We decided in the end that as it ahd other issues and the teacher said it was holding our daughter back to change it.