I tried it in sidplay2/w win32 version 2.6, and it plays well.
2 Nov 21, 2015 5:35 pm
Re: How convert .prg to .sid? (32 replies, posted in Commodore Computers)
The only differece I can see between my two tunes is that in the one with a problem I start track 1 with a block containing:
dur.40
snd.00
c-0
c-0
c-0
c-0
**END**
to produce some silence.
[edit]
I solved it.
One of my problematic tunes had only one repeating block on track 1, and many more blocks on the other tracks. I just put more of the same block on track 1 so the tracks became equally long.
The problem in the "problematic.prg" was I had two blocks in a row with only one transpose byte before. I inserted a transpose byte in front of every block, and that solved it.
But these fixes should not be necessary. A transpose byte should transpose all the following, according to the instructions. And "ff" should just repeat over and over regardless of one track being considerable shorter than the other. I don't know where the bug is, but now I know what to look out for.
The third one I had problems with I could not solve. But I don't care. It's really bad anyway. Some sort of mix'n'match with one of the demo songs in V2.0 and the bass from vanilla ice, ice ice baby...
Anyway, thanks for the SID header + DAT tip there. 
3 Nov 21, 2015 4:26 pm
Re: How convert .prg to .sid? (32 replies, posted in Commodore Computers)
Tried loading it into FC V4.0 and save from there. Same again.
Frustrating.
BTW, this is based on another track I did earlier (which plays very well in sidplay2/w), and the only thing I did was to add a few blocks, edit the bass sound, and rearange the track data somewhat. The only thing I can think of is some odd instrument parameter...
4 Nov 21, 2015 3:38 pm
Re: How convert .prg to .sid? (32 replies, posted in Commodore Computers)
No it is not a long track. I never did particularly long tracks. Mostly looping ones with a few blocks and no more than 2 rows of track data.
I have now saved the track from FC 2.1, converted it to SID, used PSID64 to convert that into a executable PRG, and loaded that into VICE and ran it. Same broken music.
I also tried to save+relocate to $1000.
I have no real C64 set up right now. It's all packed down. That would be the next step I think.
[edit]
This is the file http://madmodders.se/temp/c64/problematic.prg
Uhm, no. hold on. that did not load at all...
[edit2]
Now, it's the right file. Try it if you have the time.
5 Nov 21, 2015 3:02 pm
Re: How convert .prg to .sid? (32 replies, posted in Commodore Computers)
Well it didn't change anything. I loaded my problematic tune into the fixed V2.1 that was linked from the broken V2.0 one on csdb, and saved a new copy from V2.1
Same same.
6 Nov 21, 2015 2:42 pm
Re: How convert .prg to .sid? (32 replies, posted in Commodore Computers)
Yes most of my tunes plays just fine. I havn't figured out what's different with those that doesn't play right.
I've only got a single PRG file of this Future composer. No dedicated disk or anything.
The title/menu screen says:
Future-Composer V2.0
expanded and improved by Axiom/BB
It's the V2.0 from this D64 http://csdb.dk/release/?id=10605
And it says under goofs there
"This version of Future Composer has a broken packer"
Can that have anything to do with it perhaps?
7 Nov 21, 2015 2:14 pm
Re: How convert .prg to .sid? (32 replies, posted in Commodore Computers)
I've now tried the manual way with a textfile and so on. It's the exact same result as with PRG2SID.
0000,1800,1806 = music plays, but wrong
1800,1800,1806 = nothing
0000,1800,1803 = nothing
at $2117:
;2117 LDA #$02
;2119 STA $2174
;211C RTS
which is a bit strange, because it should be called with a JSR, and not a JMP?
And $2000 is some code in the middle between the data for track 2 and 3.
Haven't looked on the code for songs from other music software but this seems odd to me.
8 Nov 21, 2015 1:42 pm
Re: How convert .prg to .sid? (32 replies, posted in Commodore Computers)
Yes, it's the same old one I used back in 1989. 
(Only says AXIOM/BB for a short while and jumps right in to the menu.)
Do you mean I should use $1000 although the PRG starts with bytes 00 18 ?
;1800 JMP $2000
;1803 JMP $2117
;1806 LDA $2174
.
.
. and the rest...
Haven't tried VSID yet
[edit] tried it. Same thing.
9 Nov 21, 2015 1:03 pm
Re: How convert .prg to .sid? (32 replies, posted in Commodore Computers)
I've tried to use SIDEdit to convert Future composer 2 PRG files to SID, but it doesn't work.
I've also used PRG2SID, and it works (only in 32 bit envirnoment). But sometimes the result sounds like garbage. Drums sound like continuous machine gun fire, certain bass sounds are quiet and a few arpeggios is a stuck note.
I noticed PRG2SID said init is on $1800 and play on $1806. And looking in the disassembled data view, it's fairly obvious.
I tried that in SIDEdit, and set the flags to 0x0014.
But no. Only silence.
When loading a working PRG2SID-converted SID into SIDEdit, I see no difference. What's up with that?
And are there some illegal opcodes or something for certain sounds in the future composer play routine which sidplay2/w can't handle?