hi, i use a line 6 spider 4 15w amp and starting around 4 months ago i have been getting this ugly crackly and sometimes fuzzy/muffled sound. i have tried asking other forums but i don't get an answer. i have tried changing outlets and keeping the amp cool, yet nothing seems to work. i have had the thing 4 years. the problem seems to only occur when i am not playing through headphones. i have also tried doing a factory reset. should i try getting a new amp or is there a way for me to fix it at home?
Sounds like you've had the amp cranked too much for too long. I had this happen to an old MG. Being the arrogant noob I was, I thought that all amps sounded better cranked. So I had the MG all the way up on a number of occasions and then it started doing what you described. I assume this can also happen from heavy usage.

To be honest, I wouldn't bother trying to fix it. You'd be better off getting a new amp.
Personally, just get a new amp. Spider IVs aren't that good to begin with but luckily you've only got the 15w version so its not much of a loss.

I would say its not worth fixing because its not a great amp.
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