Tuning Problem

[stevewalsh77]

I recently upgraded to Logic Pro X running under El Capitan - I'd previously used Logic 8.

I use a 2010 MacPro with 25 GB RAM and a Saffire PRO26 Audio interface. Motu MTP AV Midi interface.

Since going up to Logic Pro X one of the oddest glitches I've come across is on certain songs, parts played on Logic's software instruments transpose themselves up or down by a tone. Sometimes I can open a song and it's fine - in the correct key I played it in. If I check the MIdi notes, they are still where I played them originally. It won't always affect all instruments. Whereas the Bass part will play in the correct key, the Electric Piano or strings/voice effect have transposed themselves up a tone. Sometimes closing the song and opening it again can rectify the problem, but other times the problem has persisted. Sometimes the songs are fine and it doesn't occur. I thought at first it was to do with older legacy songs being taken across from Logic 8 to Pro X, but it's also happened when I created songs in ProX. Fixes have included transposing the part up or down, but then it will sound wrong next time I open it when it's reverted to the correct key. Any ideas what this is?